This topic is a compilation of functions, operators, and conditional expressions.
To learn more about how to call functions, function call rules,
the SAFE
prefix, and special types of arguments,
see Function calls.
OPERATORS AND CONDITIONALS
Operators in GoogleSQL
GoogleSQL for Spanner supports operators. Operators are represented by special characters or keywords; they do not use function call syntax. An operator manipulates any number of data inputs, also called operands, and returns a result.
Common conventions:
 Unless otherwise specified, all operators return
NULL
when one of the operands isNULL
.  All operators will throw an error if the computation result overflows.
 For all floating point operations,
+/inf
andNaN
may only be returned if one of the operands is+/inf
orNaN
. In other cases, an error is returned.
Operator precedence
The following table lists all GoogleSQL operators from highest to lowest precedence, i.e. the order in which they will be evaluated within a statement.
Order of Precedence  Operator  Input Data Types  Name  Operator Arity 

1  Field access operator 
STRUCT JSON 
Field access operator  Binary 
Array subscript operator  ARRAY 
Array position. Must be used with OFFSET or ORDINAL —see
Array Functions
. 
Binary  
JSON subscript operator  JSON 
Field name or array position in JSON.  Binary  
2  + 
All numeric types  Unary plus  Unary 
 
All numeric types  Unary minus  Unary  
~ 
Integer or BYTES 
Bitwise not  Unary  
3  * 
All numeric types  Multiplication  Binary 
/ 
All numeric types  Division  Binary  
 
STRING , BYTES , or ARRAY<T> 
Concatenation operator  Binary  
4  + 
All numeric types  Addition  Binary 
 
All numeric types  Subtraction  Binary  
5  << 
Integer or BYTES 
Bitwise leftshift  Binary 
>> 
Integer or BYTES 
Bitwise rightshift  Binary  
6  & 
Integer or BYTES 
Bitwise and  Binary 
7  ^ 
Integer or BYTES 
Bitwise xor  Binary 
8   
Integer or BYTES 
Bitwise or  Binary 
9 (Comparison Operators)  = 
Any comparable type. See Data Types for a complete list.  Equal  Binary 
< 
Any comparable type. See Data Types for a complete list.  Less than  Binary  
> 
Any comparable type. See Data Types for a complete list.  Greater than  Binary  
<= 
Any comparable type. See Data Types for a complete list.  Less than or equal to  Binary  
>= 
Any comparable type. See Data Types for a complete list.  Greater than or equal to  Binary  
!= , <> 
Any comparable type. See Data Types for a complete list.  Not equal  Binary  
[NOT] LIKE 
STRING and BYTES 
Value does [not] match the pattern specified  Binary  
[NOT] BETWEEN 
Any comparable types. See Data Types for a complete list.  Value is [not] within the range specified  Binary  
[NOT] IN 
Any comparable types. See Data Types for a complete list.  Value is [not] in the set of values specified  Binary  
IS [NOT] NULL 
All  Value is [not] NULL 
Unary  
IS [NOT] TRUE 
BOOL 
Value is [not] TRUE . 
Unary  
IS [NOT] FALSE 
BOOL 
Value is [not] FALSE . 
Unary  
10  NOT 
BOOL 
Logical NOT 
Unary 
11  AND 
BOOL 
Logical AND 
Binary 
12  OR 
BOOL 
Logical OR 
Binary 
Operators with the same precedence are left associative. This means that those operators are grouped together starting from the left and moving right. For example, the expression:
x AND y AND z
is interpreted as
( ( x AND y ) AND z )
The expression:
x * y / z
is interpreted as:
( ( x * y ) / z )
All comparison operators have the same priority, but comparison operators are not associative. Therefore, parentheses are required in order to resolve ambiguity. For example:
(x < y) IS FALSE
Field access operator
expression.fieldname[. ...]
Description
Gets the value of a field. Alternatively known as the dot operator. Can be
used to access nested fields. For example, expression.fieldname1.fieldname2
.
Input values:
STRUCT
JSON
Return type
 For
STRUCT
: SQL data type offieldname
. If a field is not found in the struct, an error is thrown.  For
JSON
:JSON
. If a field is not found in a JSON value, a SQLNULL
is returned.
Example
In the following example, the expression is t.customer
and the
field access operations are .address
and .country
. An operation is an
application of an operator (.
) to specific operands (in this case,
address
and country
, or more specifically, t.customer
and address
,
for the first operation, and t.customer.address
and country
for the
second operation).
WITH orders AS (
SELECT STRUCT(STRUCT('Yonge Street' AS street, 'Canada' AS country) AS address) AS customer
)
SELECT t.customer.address.country FROM orders AS t;
/**
 country 
++
 Canada 
**/
Array subscript operator
array_expression[array_subscript_specifier]
array_subscript_specifier:
position_keyword(index)
position_keyword:
{ OFFSET  SAFE_OFFSET  ORDINAL  SAFE_ORDINAL }
Description
Gets a value from an array at a specific position.
Input values:
array_expression
: The input array.position_keyword(index)
: Determines where the index for the array should start and how outofrange indexes are handled. The index is an integer that represents a specific position in the array.OFFSET(index)
: The index starts at zero. Produces an error if the index is out of range. To produceNULL
instead of an error, useSAFE_OFFSET(index)
.SAFE_OFFSET(index)
: The index starts at zero. ReturnsNULL
if the index is out of range.ORDINAL(index)
: The index starts at one. Produces an error if the index is out of range. To produceNULL
instead of an error, useSAFE_ORDINAL(index)
.SAFE_ORDINAL(index)
: The index starts at one. ReturnsNULL
if the index is out of range.
Return type
T
where array_expression
is ARRAY<T>
.
Examples
In following query, the array subscript operator is used to return values at
specific position in item_array
. This query also shows what happens when you
reference an index (6
) in an array that is out of range. If the SAFE
prefix
is included, NULL
is returned, otherwise an error is produced.
WITH Items AS (SELECT ["coffee", "tea", "milk"] AS item_array)
SELECT
item_array,
item_array[OFFSET(0)] AS item_offset,
item_array[ORDINAL(1)] AS item_ordinal,
item_array[SAFE_OFFSET(6)] AS item_safe_offset
FROM Items
/*+++*
 item_array  item_offset  item_ordinal  item_safe_offset 
+++++
 [coffee, tea, milk]  coffee  coffee  NULL 
*+++*/
When you reference an index that is out of range in an array, and a positional
keyword that begins with SAFE
is not included, an error is produced.
For example:
WITH Items AS (SELECT ["coffee", "tea", "milk"] AS item_array)
SELECT
item_array[OFFSET(6)] AS item_offset
FROM Items
 Error. Array index 6 is out of bounds.
JSON subscript operator
json_expression[array_element_id]
json_expression[field_name]
Description
Gets a value of an array element or field in a JSON expression. Can be used to access nested data.
Input values:
JSON expression
: TheJSON
expression that contains an array element or field to return.[array_element_id]
: AnINT64
expression that represents a zerobased index in the array. If a negative value is entered, or the value is greater than or equal to the size of the array, or the JSON expression doesn't represent a JSON array, a SQLNULL
is returned.[field_name]
: ASTRING
expression that represents the name of a field in JSON. If the field name is not found, or the JSON expression is not a JSON object, a SQLNULL
is returned.
Return type
JSON
Example
In the following example:
json_value
is a JSON expression..class
is a JSON field access..students
is a JSON field access.[0]
is a JSON subscript expression with an element offset that accesses the zeroth element of an array in the JSON value.['name']
is a JSON subscript expression with a field name that accesses a field.
SELECT json_value.class.students[0]['name'] AS first_student
FROM
UNNEST(
[
JSON '{"class" : {"students" : [{"name" : "Jane"}]}}',
JSON '{"class" : {"students" : []}}',
JSON '{"class" : {"students" : [{"name" : "John"}, {"name": "Jamie"}]}}'])
AS json_value;
/**
 first_student 
++
 "Jane" 
 NULL 
 "John" 
**/
Arithmetic operators
All arithmetic operators accept input of numeric type T
, and the result type
has type T
unless otherwise indicated in the description below:
Name  Syntax 

Addition  X + Y 
Subtraction  X  Y 
Multiplication  X * Y 
Division  X / Y 
Unary Plus  + X 
Unary Minus   X 
NOTE: Divide by zero operations return an error. To return a different result,
consider the IEEE_DIVIDE
or SAFE_DIVIDE
functions.
Result types for Addition, Subtraction and Multiplication:
INPUT  INT64  NUMERIC  FLOAT64 

INT64  INT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
Result types for Division:
INPUT  INT64  NUMERIC  FLOAT64 

INT64  FLOAT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
Result types for Unary Plus:
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  INT64  NUMERIC  FLOAT64 
Result types for Unary Minus:
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  INT64  NUMERIC  FLOAT64 
Bitwise operators
All bitwise operators return the same type and the same length as the first operand.
Name  Syntax  Input Data Type  Description 

Bitwise not  ~ X 
Integer or BYTES 
Performs logical negation on each bit, forming the ones' complement of the given binary value. 
Bitwise or  X  Y 
X : Integer or BYTES Y : Same type as X

Takes two bit patterns of equal length and performs the logical inclusive
OR operation on each pair of the corresponding bits.
This operator throws an error if X and Y are bytes of
different lengths.

Bitwise xor  X ^ Y 
X : Integer or BYTES Y : Same type as X

Takes two bit patterns of equal length and performs the
logical exclusive OR operation on each pair of the corresponding
bits.
This operator throws an error if X and Y are bytes of
different lengths.

Bitwise and  X & Y 
X : Integer or BYTES Y : Same type as X

Takes two bit patterns of equal length and performs the
logical AND operation on each pair of the corresponding bits.
This operator throws an error if X and Y are bytes of
different lengths.

Left shift  X << Y 
X : Integer or BYTES Y : INT64

Shifts the first operand X to the left.
This operator returns
0 or a byte sequence of b'\x00'
if the second operand Y is greater than or equal to
the bit length of the first operand X (for example, 64
if X has the type INT64 ).
This operator throws an error if Y is negative. 
Right shift  X >> Y 
X : Integer or BYTES Y : INT64 
Shifts the first operand X to the right. This operator does not
do sign bit extension with a signed type (i.e. it fills vacant bits on the left
with 0 ). This operator returns
0 or a byte sequence of
b'\x00'
if the second operand Y is greater than or equal to
the bit length of the first operand X (for example, 64
if X has the type INT64 ).
This operator throws an error if Y is negative. 
Logical operators
GoogleSQL supports the AND
, OR
, and NOT
logical operators.
Logical operators allow only BOOL
or NULL
input
and use threevalued logic
to produce a result. The result can be TRUE
, FALSE
, or NULL
:
x 
y 
x AND y 
x OR y 

TRUE 
TRUE 
TRUE 
TRUE 
TRUE 
FALSE 
FALSE 
TRUE 
TRUE 
NULL 
NULL 
TRUE 
FALSE 
TRUE 
FALSE 
TRUE 
FALSE 
FALSE 
FALSE 
FALSE 
FALSE 
NULL 
FALSE 
NULL 
NULL 
TRUE 
NULL 
TRUE 
NULL 
FALSE 
FALSE 
NULL 
NULL 
NULL 
NULL 
NULL 
x 
NOT x 

TRUE 
FALSE 
FALSE 
TRUE 
NULL 
NULL 
Examples
The examples in this section reference a table called entry_table
:
/**
 entry 
++
 a 
 b 
 c 
 NULL 
**/
SELECT 'a' FROM entry_table WHERE entry = 'a'
 a => 'a' = 'a' => TRUE
 b => 'b' = 'a' => FALSE
 NULL => NULL = 'a' => NULL
/**
 entry 
++
 a 
**/
SELECT entry FROM entry_table WHERE NOT (entry = 'a')
 a => NOT('a' = 'a') => NOT(TRUE) => FALSE
 b => NOT('b' = 'a') => NOT(FALSE) => TRUE
 NULL => NOT(NULL = 'a') => NOT(NULL) => NULL
/**
 entry 
++
 b 
 c 
**/
SELECT entry FROM entry_table WHERE entry IS NULL
 a => 'a' IS NULL => FALSE
 b => 'b' IS NULL => FALSE
 NULL => NULL IS NULL => TRUE
/**
 entry 
++
 NULL 
**/
Comparison operators
Comparisons always return BOOL
. Comparisons generally
require both operands to be of the same type. If operands are of different
types, and if GoogleSQL can convert the values of those types to a
common type without loss of precision, GoogleSQL will generally coerce
them to that common type for the comparison; GoogleSQL will generally
coerce literals to the type of nonliterals, where
present. Comparable data types are defined in
Data Types.
Structs support only these comparison operators: equal
(=
), not equal (!=
and <>
), and IN
.
The comparison operators in this section cannot be used to compare
JSON
GoogleSQL literals with other JSON
GoogleSQL literals.
If you need to compare values inside of JSON
, convert the values to
SQL values first. For more information, see JSON
functions.
The following rules apply when comparing these data types:
FLOAT64
: All comparisons withNaN
returnFALSE
, except for!=
and<>
, which returnTRUE
.BOOL
:FALSE
is less thanTRUE
.STRING
: Strings are compared codepointbycodepoint, which means that canonically equivalent strings are only guaranteed to compare as equal if they have been normalized first.NULL
: The convention holds here: any operation with aNULL
input returnsNULL
.
Name  Syntax  Description 

Less Than  X < Y 
Returns TRUE if X is less than Y .

Less Than or Equal To  X <= Y 
Returns TRUE if X is less than or equal to
Y .

Greater Than  X > Y 
Returns TRUE if X is greater than Y .

Greater Than or Equal To  X >= Y 
Returns TRUE if X is greater than or equal to
Y .

Equal  X = Y 
Returns TRUE if X is equal to Y .

Not Equal  X != Y X <> Y 
Returns TRUE if X is not equal to Y .

BETWEEN 
X [NOT] BETWEEN Y AND Z 
Returns 
LIKE 
X [NOT] LIKE Y 
See the `LIKE` operator for details. 
IN 
Multiple  See the `IN` operator for details. 
When testing values that have a struct data type for
equality, it's possible that one or more fields are NULL
. In such cases:
 If all non
NULL
field values are equal, the comparison returnsNULL
.  If any non
NULL
field values are not equal, the comparison returnsFALSE
.
The following table demonstrates how struct data
types are compared when they have fields that are NULL
valued.
Struct1  Struct2  Struct1 = Struct2 

STRUCT(1, NULL) 
STRUCT(1, NULL) 
NULL 
STRUCT(1, NULL) 
STRUCT(2, NULL) 
FALSE 
STRUCT(1,2) 
STRUCT(1, NULL) 
NULL 
EXISTS
operator
EXISTS ( subquery )
Description
Returns TRUE
if the subquery produces one or more rows. Returns FALSE
if
the subquery produces zero rows. Never returns NULL
. To learn more about
how you can use a subquery with EXISTS
,
see EXISTS
subqueries.
Examples
In this example, the EXISTS
operator returns FALSE
because there are no
rows in Words
where the direction is south
:
WITH Words AS (
SELECT 'Intend' as value, 'east' as direction UNION ALL
SELECT 'Secure', 'north' UNION ALL
SELECT 'Clarity', 'west'
)
SELECT EXISTS ( SELECT value FROM Words WHERE direction = 'south' ) as result;
/**
 result 
++
 FALSE 
**/
IN
operator
The IN
operator supports the following syntax:
search_value [NOT] IN value_set
value_set:
{
(expression[, ...])
 (subquery)
 UNNEST(array_expression)
}
Description
Checks for an equal value in a set of values.
Semantic rules apply, but in general, IN
returns TRUE
if an equal value is found, FALSE
if an equal value is excluded, otherwise
NULL
. NOT IN
returns FALSE
if an equal value is found, TRUE
if an
equal value is excluded, otherwise NULL
.
search_value
: The expression that is compared to a set of values.value_set
: One or more values to compare to a search value.(expression[, ...])
: A list of expressions.(subquery)
: A subquery that returns a single column. The values in that column are the set of values. If no rows are produced, the set of values is empty.UNNEST(array_expression)
: An UNNEST operator that returns a column of values from an array expression. This is equivalent to:IN (SELECT element FROM UNNEST(array_expression) AS element)
This operator generally supports collation,
however, [NOT] IN UNNEST
does not support collation.
Semantic rules
When using the IN
operator, the following semantics apply in this order:
 Returns
FALSE
ifvalue_set
is empty.  Returns
NULL
ifsearch_value
isNULL
.  Returns
TRUE
ifvalue_set
contains a value equal tosearch_value
.  Returns
NULL
ifvalue_set
contains aNULL
.  Returns
FALSE
.
When using the NOT IN
operator, the following semantics apply in this order:
 Returns
TRUE
ifvalue_set
is empty.  Returns
NULL
ifsearch_value
isNULL
.  Returns
FALSE
ifvalue_set
contains a value equal tosearch_value
.  Returns
NULL
ifvalue_set
contains aNULL
.  Returns
TRUE
.
The semantics of:
x IN (y, z, ...)
are defined as equivalent to:
(x = y) OR (x = z) OR ...
and the subquery and array forms are defined similarly.
x NOT IN ...
is equivalent to:
NOT(x IN ...)
The UNNEST
form treats an array scan like UNNEST
in the
FROM
clause:
x [NOT] IN UNNEST(<array expression>)
This form is often used with array parameters. For example:
x IN UNNEST(@array_parameter)
See the Arrays topic for more information on how to use this syntax.
IN
can be used with multipart keys by using the struct constructor syntax.
For example:
(Key1, Key2) IN ( (12,34), (56,78) )
(Key1, Key2) IN ( SELECT (table.a, table.b) FROM table )
See the Struct Type topic for more information.
Return Data Type
BOOL
Examples
You can use these WITH
clauses to emulate temporary tables for
Words
and Items
in the following examples:
WITH Words AS (
SELECT 'Intend' as value UNION ALL
SELECT 'Secure' UNION ALL
SELECT 'Clarity' UNION ALL
SELECT 'Peace' UNION ALL
SELECT 'Intend'
)
SELECT * FROM Words;
/**
 value 
++
 Intend 
 Secure 
 Clarity 
 Peace 
 Intend 
**/
WITH
Items AS (
SELECT STRUCT('blue' AS color, 'round' AS shape) AS info UNION ALL
SELECT STRUCT('blue', 'square') UNION ALL
SELECT STRUCT('red', 'round')
)
SELECT * FROM Items;
/**
 info 
++
 {blue color, round shape} 
 {blue color, square shape} 
 {red color, round shape} 
**/
Example with IN
and an expression:
SELECT * FROM Words WHERE value IN ('Intend', 'Secure');
/**
 value 
++
 Intend 
 Secure 
 Intend 
**/
Example with NOT IN
and an expression:
SELECT * FROM Words WHERE value NOT IN ('Intend');
/**
 value 
++
 Secure 
 Clarity 
 Peace 
**/
Example with IN
, a scalar subquery, and an expression:
SELECT * FROM Words WHERE value IN ((SELECT 'Intend'), 'Clarity');
/**
 value 
++
 Intend 
 Clarity 
 Intend 
**/
Example with IN
and an UNNEST
operation:
SELECT * FROM Words WHERE value IN UNNEST(['Secure', 'Clarity']);
/**
 value 
++
 Secure 
 Clarity 
**/
Example with IN
and a struct:
SELECT
(SELECT AS STRUCT Items.info) as item
FROM
Items
WHERE (info.shape, info.color) IN (('round', 'blue'));
/**
 item 
++
 { {blue color, round shape} info } 
**/
IS
operators
IS operators return TRUE or FALSE for the condition they are testing. They never
return NULL
, even for NULL
inputs, unlike the IS_INF
and IS_NAN
functions defined in Mathematical Functions.
If NOT
is present, the output BOOL
value is
inverted.
Function Syntax  Input Data Type  Result Data Type  Description 

X IS TRUE 
BOOL 
BOOL 
Evaluates to TRUE if X evaluates to
TRUE .
Otherwise, evaluates to FALSE .

X IS NOT TRUE 
BOOL 
BOOL 
Evaluates to FALSE if X evaluates to
TRUE .
Otherwise, evaluates to TRUE .

X IS FALSE 
BOOL 
BOOL 
Evaluates to TRUE if X evaluates to
FALSE .
Otherwise, evaluates to FALSE .

X IS NOT FALSE 
BOOL 
BOOL 
Evaluates to FALSE if X evaluates to
FALSE .
Otherwise, evaluates to TRUE .

X IS NULL 
Any value type  BOOL 
Evaluates to TRUE if X evaluates to
NULL .
Otherwise evaluates to FALSE .

X IS NOT NULL 
Any value type  BOOL 
Evaluates to FALSE if X evaluates to
NULL .
Otherwise evaluates to TRUE .

X IS UNKNOWN 
BOOL 
BOOL 
Evaluates to TRUE if X evaluates to
NULL .
Otherwise evaluates to FALSE .

X IS NOT UNKNOWN 
BOOL 
BOOL 
Evaluates to FALSE if X evaluates to
NULL .
Otherwise, evaluates to TRUE .

LIKE
operator
expression_1 IS [NOT] LIKE expression_2
Description
IS LIKE
returns TRUE
if the string in the first operand expression_1
matches a pattern specified by the second operand expression_2
,
otherwise returns FALSE
.
IS NOT LIKE
returns TRUE
if the string in the first operand expression_1
does not match a pattern specified by the second operand expression_2
,
otherwise returns FALSE
.
Expressions can contain these characters:
 A percent sign (
%
) matches any number of characters or bytes.  An underscore (
_
) matches a single character or byte.  You can escape
\
,_
, or%
using two backslashes. For example,\\%
. If you are using raw strings, only a single backslash is required. For example,r'\%'
.
Return type
BOOL
Examples
The following examples illustrate how you can check to see if the string in the first operand matches a pattern specified by the second operand.
 Returns TRUE
SELECT 'apple' LIKE 'a%';
 Returns FALSE
SELECT '%a' LIKE 'apple';
 Returns FALSE
SELECT 'apple' NOT LIKE 'a%';
 Returns TRUE
SELECT '%a' NOT LIKE 'apple';
 Produces an error
SELECT NULL LIKE 'a%';
 Produces an error
SELECT 'apple' LIKE NULL;
The following example illustrates how to search multiple patterns in an array
to find a match with the LIKE
operator:
WITH Words AS
(SELECT 'Intend with clarity.' as value UNION ALL
SELECT 'Secure with intention.' UNION ALL
SELECT 'Clarity and security.')
SELECT value
FROM Words
WHERE ARRAY_INCLUDES(['%ity%', '%and%'], pattern>(Words.value LIKE pattern));
/*+
 value 
++
 Intend with clarity. 
 Clarity and security. 
+*/
Concatenation operator
The concatenation operator combines multiple values into one.
Function Syntax  Input Data Type  Result Data Type 

STRING  STRING [  ... ] 
STRING 
STRING 
BYTES  BYTES [  ... ] 
BYTES 
BYTES 
ARRAY<T>  ARRAY<T> [  ... ] 
ARRAY<T> 
ARRAY<T> 
WITH
expression
WITH(variable_assignment[, ...], result_expression)
variable_assignment:
variable_name AS expression
Description
Create one or more variables. Each variable can be used in subsequent
expressions within the WITH
expression. Returns the value of
result_expression
.
variable_assignment
: Introduces a variable. The variable name must be unique within a givenWITH
expression. Each expression can reference the variables that come before it. For example, if you create variablea
, then follow it with variableb
, you can referencea
inside ofb
's expression.variable_name
: The name of the variable.expression
: The value to assign to the variable.
result_expression
: An expression that is theWITH
expression's result.result_expression
can use all of the variables defined before it.
Return Type
 The type of the
result_expression
.
Requirements and Caveats
 A given variable may only be assigned once in a given
WITH
clause.  Variables created during
WITH
may not be used in aggregate function arguments. For example,WITH(a AS ..., SUM(a))
produces an error.  Volatile expressions behave as if they are evaluated only once.
Examples
The following example first concatenates variable a
with b
, then variable
b
with c
:
SELECT WITH(a AS '123',  a is '123'
b AS CONCAT(a, '456'),  b is '123456'
c AS '789',  c is '789'
CONCAT(b, c)) AS result;  b + c is '123456789'
/**
 result 
++
 '123456789' 
**/
Aggregate function results can be stored in variables. In this example, an average is computed:
SELECT WITH(s AS SUM(input), c AS COUNT(input), s/c)
FROM UNNEST([1.0, 2.0, 3.0]) AS input;
/**
 result 
++
 2.0 
**/
Variables cannot be used in aggregate function call arguments:
SELECT WITH(diff AS a  b, AVG(diff))
FROM UNNEST([
STRUCT(1 AS a, 2 AS b),
STRUCT(3 AS a, 4 AS b),
STRUCT(5 AS a, 6 AS b),
]);
 ERROR: WITH variables like 'diff' cannot be used in aggregate or analytic
 function arguments.
Conditional expressions in GoogleSQL
GoogleSQL for Spanner supports conditional expressions. Conditional expressions impose constraints on the evaluation order of their inputs. In essence, they are evaluated left to right, with shortcircuiting, and only evaluate the output value that was chosen. In contrast, all inputs to regular functions are evaluated before calling the function. Shortcircuiting in conditional expressions can be exploited for error handling or performance tuning.
CASE expr
CASE expr
WHEN expr_to_match THEN result
[ ... ]
[ ELSE else_result ]
END
Description
Compares expr
to expr_to_match
of each successive WHEN
clause and returns
the first result where this comparison evaluates to TRUE
. The remaining WHEN
clauses and else_result
aren't evaluated.
If the expr = expr_to_match
comparison evaluates to FALSE
or NULL
for all
WHEN
clauses, returns the evaluation of else_result
if present; if
else_result
isn't present, then returns NULL
.
Consistent with equality comparisons elsewhere, if both
expr
and expr_to_match
are NULL
, then expr = expr_to_match
evaluates to
NULL
, which returns else_result
. If a CASE statement needs to distinguish a
NULL
value, then the alternate CASE syntax should be used.
expr
and expr_to_match
can be any type. They must be implicitly
coercible to a common supertype; equality comparisons are
done on coerced values. There may be multiple result
types. result
and
else_result
expressions must be coercible to a common supertype.
Return Data Type
Supertype of result
[, ...] and else_result
.
Example
WITH Numbers AS (
SELECT 90 as A, 2 as B UNION ALL
SELECT 50, 8 UNION ALL
SELECT 60, 6 UNION ALL
SELECT 50, 10
)
SELECT
A,
B,
CASE A
WHEN 90 THEN 'red'
WHEN 50 THEN 'blue'
ELSE 'green'
END
AS result
FROM Numbers
/**
 A  B  result 
++
 90  2  red 
 50  8  blue 
 60  6  green 
 50  10  blue 
**/
CASE
CASE
WHEN condition THEN result
[ ... ]
[ ELSE else_result ]
END
Description
Evaluates the condition of each successive WHEN
clause and returns the
first result where the condition evaluates to TRUE
; any remaining WHEN
clauses and else_result
aren't evaluated.
If all conditions evaluate to FALSE
or NULL
, returns evaluation of
else_result
if present; if else_result
isn't present, then returns NULL
.
For additional rules on how values are evaluated, see the threevalued logic table in Logical operators.
condition
must be a boolean expression. There may be multiple result
types.
result
and else_result
expressions must be implicitly coercible to a common
supertype.
Return Data Type
Supertype of result
[, ...] and else_result
.
Example
WITH Numbers AS (
SELECT 90 as A, 2 as B UNION ALL
SELECT 50, 6 UNION ALL
SELECT 20, 10
)
SELECT
A,
B,
CASE
WHEN A > 60 THEN 'red'
WHEN B = 6 THEN 'blue'
ELSE 'green'
END
AS result
FROM Numbers
/**
 A  B  result 
++
 90  2  red 
 50  6  blue 
 20  10  green 
**/
COALESCE
COALESCE(expr[, ...])
Description
Returns the value of the first nonNULL
expression, if any, otherwise
NULL
. The remaining expressions aren't evaluated. An input expression can be
any type. There may be multiple input expression types.
All input expressions must be implicitly coercible to a common
supertype.
Return Data Type
Supertype of expr
[, ...].
Examples
SELECT COALESCE('A', 'B', 'C') as result
/**
 result 
++
 A 
**/
SELECT COALESCE(NULL, 'B', 'C') as result
/**
 result 
++
 B 
**/
IF
IF(expr, true_result, else_result)
Description
If expr
evaluates to TRUE
, returns true_result
, else returns the
evaluation for else_result
. else_result
isn't evaluated if expr
evaluates
to TRUE
. true_result
isn't evaluated if expr
evaluates to FALSE
or
NULL
.
expr
must be a boolean expression. true_result
and else_result
must be coercible to a common supertype.
Return Data Type
Supertype of true_result
and else_result
.
Example
WITH Numbers AS (
SELECT 10 as A, 20 as B UNION ALL
SELECT 50, 30 UNION ALL
SELECT 60, 60
)
SELECT
A,
B,
IF(A < B, 'true', 'false') AS result
FROM Numbers
/**
 A  B  result 
++
 10  20  true 
 50  30  false 
 60  60  false 
**/
IFNULL
IFNULL(expr, null_result)
Description
If expr
evaluates to NULL
, returns null_result
. Otherwise, returns
expr
. If expr
doesn't evaluate to NULL
, null_result
isn't evaluated.
expr
and null_result
can be any type and must be implicitly coercible to
a common supertype. Synonym for
COALESCE(expr, null_result)
.
Return Data Type
Supertype of expr
or null_result
.
Examples
SELECT IFNULL(NULL, 0) as result
/**
 result 
++
 0 
**/
SELECT IFNULL(10, 0) as result
/**
 result 
++
 10 
**/
NULLIF
NULLIF(expr, expr_to_match)
Description
Returns NULL
if expr = expr_to_match
evaluates to TRUE
, otherwise
returns expr
.
expr
and expr_to_match
must be implicitly coercible to a
common supertype, and must be comparable.
Return Data Type
Supertype of expr
and expr_to_match
.
Example
SELECT NULLIF(0, 0) as result
/**
 result 
++
 NULL 
**/
SELECT NULLIF(10, 0) as result
/**
 result 
++
 10 
**/
FUNCTIONS
Aggregate functions in GoogleSQL
GoogleSQL for Spanner supports the following general aggregate functions. To learn about the syntax for aggregate function calls, see Aggregate function calls.
Function list
Name  Summary 

ANY_VALUE

Gets an expression for some row. 
ARRAY_AGG

Gets an array of values. 
ARRAY_CONCAT_AGG

Concatenates arrays and returns a single array as a result. 
AVG

Gets the average of nonNULL values.

BIT_AND

Performs a bitwise AND operation on an expression. 
BIT_OR

Performs a bitwise OR operation on an expression. 
BIT_XOR

Performs a bitwise XOR operation on an expression. 
COUNT

Gets the number of rows in the input, or the number of rows with an
expression evaluated to any value other than NULL .

COUNTIF

Gets the count of TRUE values for an expression.

LOGICAL_AND

Gets the logical AND of all nonNULL expressions.

LOGICAL_OR

Gets the logical OR of all nonNULL expressions.

MAX

Gets the maximum nonNULL value.

MIN

Gets the minimum nonNULL value.

STRING_AGG

Concatenates nonNULL STRING or
BYTES values.

SUM

Gets the sum of nonNULL values.

ANY_VALUE
ANY_VALUE(
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns expression
for some row chosen from the group. Which row is chosen is
nondeterministic, not random. Returns NULL
when the input produces no
rows. Returns NULL
when expression
is NULL
for all rows in the group.
ANY_VALUE
behaves as if IGNORE NULLS
is specified;
rows for which expression
is NULL
are not considered and won't be
selected.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
Any
Returned Data Types
Matches the input data type.
Examples
SELECT ANY_VALUE(fruit) as any_value
FROM UNNEST(["apple", "banana", "pear"]) as fruit;
/**
 any_value 
++
 apple 
**/
WITH
Store AS (
SELECT 20 AS sold, "apples" AS fruit
UNION ALL
SELECT 30 AS sold, "pears" AS fruit
UNION ALL
SELECT 30 AS sold, "bananas" AS fruit
UNION ALL
SELECT 10 AS sold, "oranges" AS fruit
)
SELECT ANY_VALUE(fruit HAVING MAX sold) AS a_highest_selling_fruit FROM Store;
/**
 a_highest_selling_fruit 
++
 pears 
**/
WITH
Store AS (
SELECT 20 AS sold, "apples" AS fruit
UNION ALL
SELECT 30 AS sold, "pears" AS fruit
UNION ALL
SELECT 30 AS sold, "bananas" AS fruit
UNION ALL
SELECT 10 AS sold, "oranges" AS fruit
)
SELECT ANY_VALUE(fruit HAVING MIN sold) AS a_lowest_selling_fruit FROM Store;
/**
 a_lowest_selling_fruit 
++
 oranges 
**/
ARRAY_AGG
ARRAY_AGG(
[ DISTINCT ]
expression
[ { IGNORE  RESPECT } NULLS ]
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns an ARRAY of expression
values.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
All data types except ARRAY.
Returned Data Types
ARRAY
If there are zero input rows, this function returns NULL
.
Examples
SELECT ARRAY_AGG(x) AS array_agg FROM UNNEST([2, 1,2, 3, 2, 1, 2]) AS x;
/**
 array_agg 
++
 [2, 1, 2, 3, 2, 1, 2] 
**/
SELECT ARRAY_AGG(DISTINCT x) AS array_agg
FROM UNNEST([2, 1, 2, 3, 2, 1, 2]) AS x;
/**
 array_agg 
++
 [2, 1, 2, 3] 
**/
SELECT ARRAY_AGG(x IGNORE NULLS) AS array_agg
FROM UNNEST([NULL, 1, 2, 3, 2, 1, NULL]) AS x;
/**
 array_agg 
++
 [1, 2, 3, 2, 1] 
**/
WITH vals AS
(
SELECT 1 x, 'a' y UNION ALL
SELECT 1 x, 'b' y UNION ALL
SELECT 2 x, 'a' y UNION ALL
SELECT 2 x, 'c' y
)
SELECT x, ARRAY_AGG(y) as array_agg
FROM vals
GROUP BY x;
/**
 x  array_agg 
++
 1  [a, b] 
 2  [a, c] 
**/
ARRAY_CONCAT_AGG
ARRAY_CONCAT_AGG(
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Concatenates elements from expression
of type ARRAY
, returning a single
array as a result.
This function ignores NULL
input arrays, but respects the NULL
elements in
nonNULL
input arrays. Returns NULL
if there are zero input rows or
expression
evaluates to NULL
for all rows.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
ARRAY
Returned Data Types
ARRAY
Examples
SELECT ARRAY_CONCAT_AGG(x) AS array_concat_agg FROM (
SELECT [NULL, 1, 2, 3, 4] AS x
UNION ALL SELECT NULL
UNION ALL SELECT [5, 6]
UNION ALL SELECT [7, 8, 9]
);
/**
 array_concat_agg 
++
 [NULL, 1, 2, 3, 4, 5, 6, 7, 8, 9] 
**/
AVG
AVG(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the average of nonNULL
values in an aggregated group.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Caveats:
 If the aggregated group is empty or the argument is
NULL
for all rows in the group, returnsNULL
.  If the argument is
NaN
for any row in the group, returnsNaN
.  If the argument is
[+]Infinity
for any row in the group, returns either[+]Infinity
orNaN
.  If there is numeric overflow, produces an error.
 If a floatingpoint type is returned, the result is nondeterministic, which means you might receive a different result each time you use this function.
Supported Argument Types
 Any numeric input type
Returned Data Types
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
Examples
SELECT AVG(x) as avg
FROM UNNEST([0, 2, 4, 4, 5]) as x;
/**
 avg 
++
 3 
**/
SELECT AVG(DISTINCT x) AS avg
FROM UNNEST([0, 2, 4, 4, 5]) AS x;
/**
 avg 
++
 2.75 
**/
BIT_AND
BIT_AND(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Performs a bitwise AND operation on expression
and returns the result.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
 INT64
Returned Data Types
INT64
Examples
SELECT BIT_AND(x) as bit_and FROM UNNEST([0xF001, 0x00A1]) as x;
/**
 bit_and 
++
 1 
**/
BIT_OR
BIT_OR(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Performs a bitwise OR operation on expression
and returns the result.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
 INT64
Returned Data Types
INT64
Examples
SELECT BIT_OR(x) as bit_or FROM UNNEST([0xF001, 0x00A1]) as x;
/**
 bit_or 
++
 61601 
**/
BIT_XOR
BIT_XOR(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Performs a bitwise XOR operation on expression
and returns the result.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
 INT64
Returned Data Types
INT64
Examples
SELECT BIT_XOR(x) AS bit_xor FROM UNNEST([5678, 1234]) AS x;
/**
 bit_xor 
++
 4860 
**/
SELECT BIT_XOR(x) AS bit_xor FROM UNNEST([1234, 5678, 1234]) AS x;
/**
 bit_xor 
++
 5678 
**/
SELECT BIT_XOR(DISTINCT x) AS bit_xor FROM UNNEST([1234, 5678, 1234]) AS x;
/**
 bit_xor 
++
 4860 
**/
COUNT
1.
COUNT(*)
2.
COUNT(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
 Returns the number of rows in the input.
 Returns the number of rows with
expression
evaluated to any value other thanNULL
.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
expression
can be any data type. If
DISTINCT
is present, expression
can only be a data type that is
groupable.
Return Data Types
INT64
Examples
You can use the COUNT
function to return the number of rows in a table or the
number of distinct values of an expression. For example:
SELECT
COUNT(*) AS count_star,
COUNT(DISTINCT x) AS count_dist_x
FROM UNNEST([1, 4, 4, 5]) AS x;
/*+*
 count_star  count_dist_x 
+++
 4  3 
*+*/
SELECT COUNT(*) AS count_star, COUNT(x) AS count_x
FROM UNNEST([1, 4, NULL, 4, 5]) AS x;
/*+*
 count_star  count_x 
+++
 5  4 
*+*/
If you want to count the number of distinct values of an expression for which a certain condition is satisfied, this is one recipe that you can use:
COUNT(DISTINCT IF(condition, expression, NULL))
Here, IF
will return the value of expression
if condition
is TRUE
, or
NULL
otherwise. The surrounding COUNT(DISTINCT ...)
will ignore the NULL
values, so it will count only the distinct values of expression
for which
condition
is TRUE
.
For example, to count the number of distinct positive values of x
:
SELECT COUNT(DISTINCT IF(x > 0, x, NULL)) AS distinct_positive
FROM UNNEST([1, 2, 4, 1, 5, 4, 1, 3, 6, 1]) AS x;
/**
 distinct_positive 
++
 3 
**/
Or to count the number of distinct dates on which a certain kind of event occurred:
WITH Events AS (
SELECT DATE '20210101' AS event_date, 'SUCCESS' AS event_type
UNION ALL
SELECT DATE '20210102' AS event_date, 'SUCCESS' AS event_type
UNION ALL
SELECT DATE '20210102' AS event_date, 'FAILURE' AS event_type
UNION ALL
SELECT DATE '20210103' AS event_date, 'SUCCESS' AS event_type
UNION ALL
SELECT DATE '20210104' AS event_date, 'FAILURE' AS event_type
UNION ALL
SELECT DATE '20210104' AS event_date, 'FAILURE' AS event_type
)
SELECT
COUNT(DISTINCT IF(event_type = 'FAILURE', event_date, NULL))
AS distinct_dates_with_failures
FROM Events;
/**
 distinct_dates_with_failures 
++
 2 
**/
COUNTIF
COUNTIF(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the count of TRUE
values for expression
. Returns 0
if there are
zero input rows, or if expression
evaluates to FALSE
or NULL
for all rows.
Since expression
must be a BOOL
, the form
COUNTIF(DISTINCT ...)
is generally not useful: there is only one distinct
value of TRUE
. So COUNTIF(DISTINCT ...)
will return 1 if expression
evaluates to TRUE
for one or more input rows, or 0 otherwise.
Usually when someone wants to combine COUNTIF
and DISTINCT
, they
want to count the number of distinct values of an expression for which a certain
condition is satisfied. One recipe to achieve this is the following:
COUNT(DISTINCT IF(condition, expression, NULL))
Note that this uses COUNT
, not COUNTIF
; the IF
part has been moved inside.
To learn more, see the examples for COUNT
.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
BOOL
Return Data Types
INT64
Examples
SELECT COUNTIF(x<0) AS num_negative, COUNTIF(x>0) AS num_positive
FROM UNNEST([5, 2, 3, 6, 10, 7, 4, 0]) AS x;
/*+*
 num_negative  num_positive 
+++
 3  4 
*+*/
LOGICAL_AND
LOGICAL_AND(
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the logical AND of all nonNULL
expressions. Returns NULL
if there
are zero input rows or expression
evaluates to NULL
for all rows.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
BOOL
Return Data Types
BOOL
Examples
LOGICAL_AND
returns FALSE
because not all of the values in the array are
less than 3.
SELECT LOGICAL_AND(x < 3) AS logical_and FROM UNNEST([1, 2, 4]) AS x;
/**
 logical_and 
++
 FALSE 
**/
LOGICAL_OR
LOGICAL_OR(
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the logical OR of all nonNULL
expressions. Returns NULL
if there
are zero input rows or expression
evaluates to NULL
for all rows.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
BOOL
Return Data Types
BOOL
Examples
LOGICAL_OR
returns TRUE
because at least one of the values in the array is
less than 3.
SELECT LOGICAL_OR(x < 3) AS logical_or FROM UNNEST([1, 2, 4]) AS x;
/**
 logical_or 
++
 TRUE 
**/
MAX
MAX(
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the maximum nonNULL
value in an aggregated group.
Caveats:
 If the aggregated group is empty or the argument is
NULL
for all rows in the group, returnsNULL
.  If the argument is
NaN
for any row in the group, returnsNaN
.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
Any orderable data type except for ARRAY
.
Return Data Types
The data type of the input values.
Examples
SELECT MAX(x) AS max
FROM UNNEST([8, 37, 55, 4]) AS x;
/**
 max 
++
 55 
**/
MIN
MIN(
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the minimum nonNULL
value in an aggregated group.
Caveats:
 If the aggregated group is empty or the argument is
NULL
for all rows in the group, returnsNULL
.  If the argument is
NaN
for any row in the group, returnsNaN
.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
Any orderable data type except for ARRAY
.
Return Data Types
The data type of the input values.
Examples
SELECT MIN(x) AS min
FROM UNNEST([8, 37, 4, 55]) AS x;
/**
 min 
++
 4 
**/
STRING_AGG
STRING_AGG(
[ DISTINCT ]
expression [, delimiter]
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns a value (either STRING
or BYTES
) obtained by concatenating
nonNULL
values. Returns NULL
if there are zero input rows or expression
evaluates to NULL
for all rows.
If a delimiter
is specified, concatenated values are separated by that
delimiter; otherwise, a comma is used as a delimiter.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Supported Argument Types
Either STRING
or BYTES
.
Return Data Types
Either STRING
or BYTES
.
Examples
SELECT STRING_AGG(fruit) AS string_agg
FROM UNNEST(["apple", NULL, "pear", "banana", "pear"]) AS fruit;
/**
 string_agg 
++
 apple,pear,banana,pear 
**/
SELECT STRING_AGG(fruit, " & ") AS string_agg
FROM UNNEST(["apple", "pear", "banana", "pear"]) AS fruit;
/**
 string_agg 
++
 apple & pear & banana & pear 
**/
SELECT STRING_AGG(DISTINCT fruit, " & ") AS string_agg
FROM UNNEST(["apple", "pear", "banana", "pear"]) AS fruit;
/**
 string_agg 
++
 apple & pear & banana 
**/
SUM
SUM(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the sum of nonNULL
values in an aggregated group.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Caveats:
 If the aggregated group is empty or the argument is
NULL
for all rows in the group, returnsNULL
.  If the argument is
NaN
for any row in the group, returnsNaN
.  If the argument is
[+]Infinity
for any row in the group, returns either[+]Infinity
orNaN
.  If there is numeric overflow, produces an error.
 If a floatingpoint type is returned, the result is nondeterministic, which means you might receive a different result each time you use this function.
Supported Argument Types
 Any supported numeric data type
Return Data Types
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  INT64  NUMERIC  FLOAT64 
Examples
SELECT SUM(x) AS sum
FROM UNNEST([1, 2, 3, 4, 5, 4, 3, 2, 1]) AS x;
/**
 sum 
++
 25 
**/
SELECT SUM(DISTINCT x) AS sum
FROM UNNEST([1, 2, 3, 4, 5, 4, 3, 2, 1]) AS x;
/**
 sum 
++
 15 
**/
SELECT SUM(x) AS sum
FROM UNNEST([]) AS x;
/**
 sum 
++
 NULL 
**/
Statistical aggregate functions in GoogleSQL
GoogleSQL for Spanner supports statistical aggregate functions. To learn about the syntax for aggregate function calls, see Aggregate function calls.
Function list
Name  Summary 

STDDEV

An alias of the STDDEV_SAMP function.

STDDEV_SAMP

Computes the sample (unbiased) standard deviation of the values. 
VAR_SAMP

Computes the sample (unbiased) variance of the values. 
VARIANCE

An alias of VAR_SAMP .

STDDEV
STDDEV(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
An alias of STDDEV_SAMP.
STDDEV_SAMP
STDDEV_SAMP(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the sample (unbiased) standard deviation of the values. The return
result is between 0
and +Inf
.
All numeric types are supported. If the
input is NUMERIC
then the internal aggregation is
stable with the final output converted to a FLOAT64
.
Otherwise the input is converted to a FLOAT64
before aggregation, resulting in a potentially unstable result.
This function ignores any NULL
inputs. If there are fewer than two nonNULL
inputs, this function returns NULL
.
NaN
is produced if:
 Any input value is
NaN
 Any input value is positive infinity or negative infinity.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Return Data Type
FLOAT64
Examples
SELECT STDDEV_SAMP(x) AS results FROM UNNEST([10, 14, 18]) AS x
/**
 results 
++
 4 
**/
SELECT STDDEV_SAMP(x) AS results FROM UNNEST([10, 14, NULL]) AS x
/**
 results 
++
 2.8284271247461903 
**/
SELECT STDDEV_SAMP(x) AS results FROM UNNEST([10, NULL]) AS x
/**
 results 
++
 NULL 
**/
SELECT STDDEV_SAMP(x) AS results FROM UNNEST([NULL]) AS x
/**
 results 
++
 NULL 
**/
SELECT STDDEV_SAMP(x) AS results FROM UNNEST([10, 14, CAST('Infinity' as FLOAT64)]) AS x
/**
 results 
++
 NaN 
**/
VAR_SAMP
VAR_SAMP(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
Returns the sample (unbiased) variance of the values. The return result is
between 0
and +Inf
.
All numeric types are supported. If the
input is NUMERIC
then the internal aggregation is
stable with the final output converted to a FLOAT64
.
Otherwise the input is converted to a FLOAT64
before aggregation, resulting in a potentially unstable result.
This function ignores any NULL
inputs. If there are fewer than two nonNULL
inputs, this function returns NULL
.
NaN
is produced if:
 Any input value is
NaN
 Any input value is positive infinity or negative infinity.
To learn more about the optional aggregate clauses that you can pass into this function, see Aggregate function calls.
Return Data Type
FLOAT64
Examples
SELECT VAR_SAMP(x) AS results FROM UNNEST([10, 14, 18]) AS x
/**
 results 
++
 16 
**/
SELECT VAR_SAMP(x) AS results FROM UNNEST([10, 14, NULL]) AS x
/**
 results 
++
 8 
**/
SELECT VAR_SAMP(x) AS results FROM UNNEST([10, NULL]) AS x
/**
 results 
++
 NULL 
**/
SELECT VAR_SAMP(x) AS results FROM UNNEST([NULL]) AS x
/**
 results 
++
 NULL 
**/
SELECT VAR_SAMP(x) AS results FROM UNNEST([10, 14, CAST('Infinity' as FLOAT64)]) AS x
/**
 results 
++
 NaN 
**/
VARIANCE
VARIANCE(
[ DISTINCT ]
expression
[ HAVING { MAX  MIN } expression2 ]
)
Description
An alias of VAR_SAMP.
Bit functions in GoogleSQL
GoogleSQL for Spanner supports the following bit functions.
Function list
Name  Summary 

BIT_COUNT

Gets the number of bits that are set in an input expression. 
BIT_REVERSE

Reverses the bits in an integer and optionally preserves its sign. 
BIT_COUNT
BIT_COUNT(expression)
Description
The input, expression
, must be an
integer or BYTES
.
Returns the number of bits that are set in the input expression
.
For signed integers, this is the number of bits in two's complement form.
Return Data Type
INT64
Example
SELECT a, BIT_COUNT(a) AS a_bits, FORMAT("%T", b) as b, BIT_COUNT(b) AS b_bits
FROM UNNEST([
STRUCT(0 AS a, b'' AS b), (0, b'\x00'), (5, b'\x05'), (8, b'\x00\x08'),
(0xFFFF, b'\xFF\xFF'), (2, b'\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFE'),
(1, b'\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF'),
(NULL, b'\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF')
]) AS x;
/*+++*
 a  a_bits  b  b_bits 
+++++
 0  0  b""  0 
 0  0  b"\x00"  0 
 5  2  b"\x05"  2 
 8  1  b"\x00\x08"  1 
 65535  16  b"\xff\xff"  16 
 2  63  b"\xff\xff\xff\xff\xff\xff\xff\xfe"  63 
 1  64  b"\xff\xff\xff\xff\xff\xff\xff\xff"  64 
 NULL  NULL  b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"  80 
*+++*/
BIT_REVERSE
BIT_REVERSE(value, [preserve_sign])
Description
Takes an integer value and returns its bitreversed version. When
preserve_sign
is TRUE
, this function provides the same bitreversal
algorithm used in bitreversed sequence. See Bitreversed sequence.
If the input value is NULL
, the function returns NULL
.
Arguments:
value
: The integer to bit reverse.Sequence
only supportsINT64
.preserve_sign
:TRUE
to exclude the sign bit, otherwiseFALSE
.
Return Data Type
The same data type as value
.
Example
SELECT BIT_REVERSE(100, true) AS results
/**
 Results 
++
 1369094286720630784 
**/
SELECT BIT_REVERSE(100, false) AS results
/**
 Results 
++
 2738188573441261568 
**/
SELECT BIT_REVERSE(100, true) AS results
/**
 Results 
++
 7133701809754865665 
**/
SELECT BIT_REVERSE(100, false) AS results
/**
 Results 
++
 4179340454199820287 
**/
Conversion functions in GoogleSQL
GoogleSQL for Spanner supports conversion functions. These data type conversions are explicit, but some conversions can happen implicitly. You can learn more about implicit and explicit conversion here.
Function list
Name  Summary 

CAST

Convert the results of an expression to the given type. 
SAFE_CAST

Similar to the CAST function, but returns NULL
when a runtime error is produced.

CAST
CAST(expression AS typename)
Description
Cast syntax is used in a query to indicate that the result type of an expression should be converted to some other type.
When using CAST
, a query can fail if GoogleSQL is unable to perform
the cast. If you want to protect your queries from these types of errors, you
can use SAFE_CAST.
Casts between supported types that do not successfully map from the original
value to the target domain produce runtime errors. For example, casting
BYTES
to STRING
where the byte sequence is not valid UTF8 results in a
runtime error.
Examples
The following query results in "true"
if x
is 1
, "false"
for any other
nonNULL
value, and NULL
if x
is NULL
.
CAST(x=1 AS STRING)
CAST AS ARRAY
CAST(expression AS ARRAY<element_type>)
Description
GoogleSQL supports casting to ARRAY
. The
expression
parameter can represent an expression for these data types:
ARRAY
Conversion rules
From  To  Rule(s) when casting x 

ARRAY 
ARRAY 
Must be the exact same array type. 
CAST AS BOOL
CAST(expression AS BOOL)
Description
GoogleSQL supports casting to BOOL
. The
expression
parameter can represent an expression for these data types:
INT64
BOOL
STRING
Conversion rules
From  To  Rule(s) when casting x 

INT64  BOOL 
Returns FALSE if x is 0 ,
TRUE otherwise.

STRING 
BOOL 
Returns TRUE if x is "true" and
FALSE if x is "false" All other values of x are invalid and throw an error instead
of casting to a boolean.A string is caseinsensitive when converting to a boolean. 
CAST AS BYTES
CAST(expression AS BYTES)
Description
GoogleSQL supports casting to BYTES
. The
expression
parameter can represent an expression for these data types:
BYTES
STRING
Conversion rules
From  To  Rule(s) when casting x 

STRING 
BYTES 
Strings are cast to bytes using UTF8 encoding. For example, the string "©", when cast to bytes, would become a 2byte sequence with the hex values C2 and A9. 
CAST AS DATE
CAST(expression AS DATE)
Description
GoogleSQL supports casting to DATE
. The expression
parameter can represent an expression for these data types:
STRING
TIMESTAMP
Conversion rules
From  To  Rule(s) when casting x 

STRING 
DATE 
When casting from string to date, the string must conform to the supported date literal format, and is independent of time zone. If the string expression is invalid or represents a date that is outside of the supported min/max range, then an error is produced. 
TIMESTAMP 
DATE 
Casting from a timestamp to date effectively truncates the timestamp as of the default time zone. 
CAST AS FLOAT64
CAST(expression AS FLOAT64)
Description
GoogleSQL supports casting to floating point types.
The expression
parameter can represent an expression for these data types:
INT64
FLOAT64
NUMERIC
STRING
Conversion rules
From  To  Rule(s) when casting x 

INT64  FLOAT64  Returns a close but potentially not exact floating point value. 
NUMERIC 
FLOAT64 
NUMERIC will convert to the closest floating point number
with a possible loss of precision.

STRING 
FLOAT64 
Returns x as a floating point value, interpreting it as
having the same form as a valid floating point literal.
Also supports casts from "[+,]inf" to
[,]Infinity ,
"[+,]infinity" to [,]Infinity , and
"[+,]nan" to NaN .
Conversions are caseinsensitive.

CAST AS INT64
CAST(expression AS INT64)
Description
GoogleSQL supports casting to integer types.
The expression
parameter can represent an expression for these data types:
INT64
FLOAT64
NUMERIC
BOOL
STRING
Conversion rules
From  To  Rule(s) when casting x 

FLOAT64  INT64 
Returns the closest integer value. Halfway cases such as 1.5 or 0.5 round away from zero. 
BOOL 
INT64 
Returns 1 if x is TRUE ,
0 otherwise.

STRING 
INT64 
A hex string can be cast to an integer. For example,
0x123 to 291 or 0x123 to
291 .

Examples
If you are working with hex strings (0x123
), you can cast those strings as
integers:
SELECT '0x123' as hex_value, CAST('0x123' as INT64) as hex_to_int;
/*+*
 hex_value  hex_to_int 
+++
 0x123  291 
*+*/
SELECT '0x123' as hex_value, CAST('0x123' as INT64) as hex_to_int;
/*+*
 hex_value  hex_to_int 
+++
 0x123  291 
*+*/
CAST AS NUMERIC
CAST(expression AS NUMERIC)
Description
GoogleSQL supports casting to NUMERIC
. The
expression
parameter can represent an expression for these data types:
INT64
FLOAT64
NUMERIC
STRING
Conversion rules
From  To  Rule(s) when casting x 

FLOAT64  NUMERIC 
The floating point number will round
half away from zero.
Casting a NaN , +inf or
inf will return an error. Casting a value outside the range
of NUMERIC returns an overflow error.

STRING 
NUMERIC 
The numeric literal contained in the string must not exceed
the maximum precision or range of the NUMERIC
type, or an error will occur. If the number of digits
after the decimal point exceeds nine, then the resulting
NUMERIC value will round
half away from zero.
to have nine digits after the decimal point.

CAST AS STRING
CAST(expression AS STRING)
Description
GoogleSQL supports casting to STRING
. The
expression
parameter can represent an expression for these data types:
INT64
FLOAT64
NUMERIC
BOOL
BYTES
DATE
TIMESTAMP
STRING
Conversion rules
From  To  Rule(s) when casting x 

FLOAT64  STRING 
Returns an approximate string representation. A returned
NaN or 0 will not be signed. 
BOOL 
STRING 
Returns "true" if x is TRUE ,
"false" otherwise. 
BYTES 
STRING 
Returns x interpreted as a UTF8 string.For example, the bytes literal b'\xc2\xa9' , when cast to a string,
is interpreted as UTF8 and becomes the unicode character "©".An error occurs if x is not valid UTF8. 
DATE 
STRING 
Casting from a date type to a string is independent of time zone and is
of the form YYYYMMDD .

TIMESTAMP 
STRING 
When casting from timestamp types to string, the timestamp is interpreted using the default time zone, America/Los_Angeles. The number of subsecond digits produced depends on the number of trailing zeroes in the subsecond part: the CAST function will truncate zero, three, or six digits. 
Examples
SELECT CAST(CURRENT_DATE() AS STRING) AS current_date
/**
 current_date 
++
 20210309 
**/
CAST AS STRUCT
CAST(expression AS STRUCT)
Description
GoogleSQL supports casting to STRUCT
. The
expression
parameter can represent an expression for these data types:
STRUCT
Conversion rules
From  To  Rule(s) when casting x 

STRUCT 
STRUCT 
Allowed if the following conditions are met:

CAST AS TIMESTAMP
CAST(expression AS TIMESTAMP)
Description
GoogleSQL supports casting to TIMESTAMP
. The
expression
parameter can represent an expression for these data types:
STRING
TIMESTAMP
Conversion rules
From  To  Rule(s) when casting x 

STRING 
TIMESTAMP 
When casting from string to a timestamp, string_expression
must conform to the supported timestamp literal formats, or else a runtime
error occurs. The string_expression may itself contain a
time zone.
If there is a time zone in the string_expression , that
time zone is used for conversion, otherwise the default time zone,
America/Los_Angeles, is used. If the string has fewer than six digits,
then it is implicitly widened.
An error is produced if the string_expression is invalid,
has more than six subsecond digits (i.e. precision greater than
microseconds), or represents a time outside of the supported timestamp
range.

DATE 
TIMESTAMP 
Casting from a date to a timestamp interprets date_expression
as of midnight (start of the day) in the default time zone,
America/Los_Angeles.

Examples
The following example casts a stringformatted timestamp as a timestamp:
SELECT CAST("20200602 17:00:53.110+00:00" AS TIMESTAMP) AS as_timestamp
 Results depend upon where this query was executed.
/**
 as_timestamp 
++
 20200603T00:00:53.11Z 
**/
SAFE_CAST
SAFE_CAST(expression AS typename)
Description
When using CAST
, a query can fail if GoogleSQL is unable to perform
the cast. For example, the following query generates an error:
SELECT CAST("apple" AS INT64) AS not_a_number;
If you want to protect your queries from these types of errors, you can use
SAFE_CAST
. SAFE_CAST
replaces runtime errors with NULL
s. However, during
static analysis, impossible casts between two noncastable types still produce
an error because the query is invalid.
SELECT SAFE_CAST("apple" AS INT64) AS not_a_number;
/**
 not_a_number 
++
 NULL 
**/
If you are casting from bytes to strings, you can also use the
function, SAFE_CONVERT_BYTES_TO_STRING
. Any invalid UTF8 characters
are replaced with the unicode replacement character, U+FFFD
.
Other conversion functions
You can learn more about these conversion functions elsewhere in the documentation:
Conversion function  From  To 

ARRAY_TO_STRING  ARRAY  STRING 
DATE  Various data types  DATE 
FROM_BASE32  STRING  BYTEs 
FROM_BASE64  STRING  BYTES 
FROM_HEX  STRING  BYTES 
PARSE_DATE  STRING  DATE 
PARSE_JSON  STRING  JSON 
PARSE_TIMESTAMP  STRING  TIMESTAMP 
SAFE_CONVERT_BYTES_TO_STRING  BYTES  STRING 
STRING  TIMESTAMP  STRING 
TIMESTAMP  Various data types  TIMESTAMP 
TO_BASE32  BYTES  STRING 
TO_BASE64  BYTES  STRING 
TO_HEX  BYTES  STRING 
TO_JSON  All data types  JSON 
TO_JSON_STRING  JSON  STRING 
Machine learning functions in GoogleSQL
GoogleSQL for Spanner supports the following machine learning (ML) functions.
Function list
Name  Summary 

ML.PREDICT

Apply ML computations defined by a model to each row of an input relation. 
ML.PREDICT
ML.PREDICT(input_model, input_relation)
input_model:
MODEL model_name
input_relation:
{ input_table  input_subquery }
input_table:
TABLE table_name
Description
ML.PREDICT
is a tablevalued function that helps to access registered
machine learning (ML) models and use them to generate ML predictions.
This function applies ML computations defined by a model to each row of an
input relation, and then, it returns the results of the predictions.
Supported Argument Types
input_model
: The model to use for predictions. Replacemodel_name
with the name of the model. To create a model, see CREATE_MODEL.input_relation
: A table or subquery upon which to apply ML computations. The set of columns of the input relation must include all input columns of the input model; otherwise, the input won't have enough data to generate predictions and the query won't compile. Additionally, the set can also include arbitrary passthrough columns that will be included in the output. The order of the columns in the input relation doesn't matter. The columns of the input relation and model must be coercible.input_table
: The table containing the input data for predictions, for example, a set of features. Replacetable_name
with the name of the table.input_subquery
: The subquery that's used to generate the prediction input data.
Return Type
A table with the following columns:
 Model outputs
 Passthrough columns from the input relation
Examples
The examples in this section reference a model called DiamondAppraise
and
an input table called Diamonds
with the following columns:
DiamondAppraise
model:Input columns Output columns value FLOAT64
value FLOAT64
carat FLOAT64
lower_bound FLOAT64
cut STRING
upper_bound FLOAT64
color STRING(1)
Diamonds
table:Columns Id INT64
Carat FLOAT64
Cut STRING
Color STRING
The following query predicts the value of a diamond based on the diamond's carat, cut, and color.
SELECT id, color, value
FROM ML.PREDICT(MODEL DiamondAppraise, TABLE Diamonds);
++++
 id  color  value 
++++
 1  I  280 
 2  G  447 
++++
You can use ML.PREDICT
in any DQL/DML statements, such as INSERT
or
UPDATE
. For example:
INSERT INTO AppraisedDiamond (id, color, carat, value)
SELECT
1 AS id,
color,
carat,
value
FROM
ML.PREDICT(MODEL DiamondAppraise,
(
SELECT
@carat AS carat,
@cut AS cut,
@color AS color
));
Mathematical functions in GoogleSQL
GoogleSQL for Spanner supports mathematical functions. All mathematical functions have the following behaviors:
 They return
NULL
if any of the input parameters isNULL
.  They return
NaN
if any of the arguments isNaN
.
Function list
Name  Summary 

ABS

Computes the absolute value of X .

ACOS

Computes the inverse cosine of X .

ACOSH

Computes the inverse hyperbolic cosine of X .

ASIN

Computes the inverse sine of X .

ASINH

Computes the inverse hyperbolic sine of X .

ATAN

Computes the inverse tangent of X .

ATAN2

Computes the inverse tangent of X/Y , using the signs of
X and Y to determine the quadrant.

ATANH

Computes the inverse hyperbolic tangent of X .

CEIL

Gets the smallest integral value that is not less than X .

CEILING

Synonym of CEIL .

COS

Computes the cosine of X .

COSH

Computes the hyperbolic cosine of X .

DIV

Divides integer X by integer Y .

EXP

Computes e to the power of X .

FLOOR

Gets the largest integral value that is not greater than X .

GREATEST

Gets the greatest value among X1,...,XN .

IEEE_DIVIDE

Divides X by Y , but does not generate errors for
division by zero or overflow.

IS_INF

Checks if X is positive or negative infinity.

IS_NAN

Checks if X is a NaN value.

LEAST

Gets the least value among X1,...,XN .

LN

Computes the natural logarithm of X .

LOG

Computes the natural logarithm of X or the logarithm of
X to base Y .

LOG10

Computes the natural logarithm of X to base 10.

MOD

Gets the remainder of the division of X by Y .

POW

Produces the value of X raised to the power of Y .

POWER

Synonym of POW .

ROUND

Rounds X to the nearest integer or rounds X
to N decimal places after the decimal point.

SAFE_ADD

Equivalent to the addition operator (X + Y ), but returns
NULL if overflow occurs.

SAFE_DIVIDE

Equivalent to the division operator (X / Y ), but returns
NULL if an error occurs.

SAFE_MULTIPLY

Equivalent to the multiplication operator (X * Y ),
but returns NULL if overflow occurs.

SAFE_NEGATE

Equivalent to the unary minus operator (X ), but returns
NULL if overflow occurs.

SAFE_SUBTRACT

Equivalent to the subtraction operator (X  Y ), but
returns NULL if overflow occurs.

SIGN

Produces 1 , 0, or +1 for negative, zero, and positive arguments respectively. 
SIN

Computes the sine of X .

SINH

Computes the hyperbolic sine of X .

SQRT

Computes the square root of X .

TAN

Computes the tangent of X .

TANH

Computes the hyperbolic tangent of X .

TRUNC

Rounds a number like ROUND(X) or ROUND(X, N) ,
but always rounds towards zero and never overflows.

ABS
ABS(X)
Description
Computes absolute value. Returns an error if the argument is an integer and the output value cannot be represented as the same type; this happens only for the largest negative input value, which has no positive representation.
X  ABS(X) 

25  25 
25  25 
+inf 
+inf 
inf 
+inf 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  INT64  NUMERIC  FLOAT64 
ACOS
ACOS(X)
Description
Computes the principal value of the inverse cosine of X. The return value is in the range [0,π]. Generates an error if X is a value outside of the range [1, 1].
If X is NUMERIC
then, the output is FLOAT64
.
X  ACOS(X) 

+inf 
NaN 
inf 
NaN 
NaN 
NaN 
X < 1  Error 
X > 1  Error 
ACOSH
ACOSH(X)
Description
Computes the inverse hyperbolic cosine of X. Generates an error if X is a value less than 1.
If X is NUMERIC
then, the output is FLOAT64
.
X  ACOSH(X) 

+inf 
+inf 
inf 
NaN 
NaN 
NaN 
X < 1  Error 
ASIN
ASIN(X)
Description
Computes the principal value of the inverse sine of X. The return value is in the range [π/2,π/2]. Generates an error if X is outside of the range [1, 1].
If X is NUMERIC
then, the output is FLOAT64
.
X  ASIN(X) 

+inf 
NaN 
inf 
NaN 
NaN 
NaN 
X < 1  Error 
X > 1  Error 
ASINH
ASINH(X)
Description
Computes the inverse hyperbolic sine of X. Does not fail.
If X is NUMERIC
then, the output is FLOAT64
.
X  ASINH(X) 

+inf 
+inf 
inf 
inf 
NaN 
NaN 
ATAN
ATAN(X)
Description
Computes the principal value of the inverse tangent of X. The return value is in the range [π/2,π/2]. Does not fail.
If X is NUMERIC
then, the output is FLOAT64
.
X  ATAN(X) 

+inf 
π/2 
inf 
π/2 
NaN 
NaN 
ATAN2
ATAN2(X, Y)
Description
Calculates the principal value of the inverse tangent of X/Y using the signs of the two arguments to determine the quadrant. The return value is in the range [π,π].
If Y is NUMERIC
then, the output is FLOAT64
.
X  Y  ATAN2(X, Y) 

NaN 
Any value  NaN 
Any value  NaN 
NaN 
0.0  0.0  0.0 
Positive Finite value  inf 
π 
Negative Finite value  inf 
π 
Finite value  +inf 
0.0 
+inf 
Finite value  π/2 
inf 
Finite value  π/2 
+inf 
inf 
¾π 
inf 
inf 
¾π 
+inf 
+inf 
π/4 
inf 
+inf 
π/4 
ATANH
ATANH(X)
Description
Computes the inverse hyperbolic tangent of X. Generates an error if X is outside of the range (1, 1).
If X is NUMERIC
then, the output is FLOAT64
.
X  ATANH(X) 

+inf 
NaN 
inf 
NaN 
NaN 
NaN 
X < 1  Error 
X > 1  Error 
CEIL
CEIL(X)
Description
Returns the smallest integral value that is not less than X.
X  CEIL(X) 

2.0  2.0 
2.3  3.0 
2.8  3.0 
2.5  3.0 
2.3  2.0 
2.8  2.0 
2.5  2.0 
0  0 
+inf 
+inf 
inf 
inf 
NaN 
NaN 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
CEILING
CEILING(X)
Description
Synonym of CEIL(X)
COS
COS(X)
Description
Computes the cosine of X where X is specified in radians. Never fails.
X  COS(X) 

+inf 
NaN 
inf 
NaN 
NaN 
NaN 
COSH
COSH(X)
Description
Computes the hyperbolic cosine of X where X is specified in radians. Generates an error if overflow occurs.
If X is NUMERIC
then, the output is FLOAT64
.
X  COSH(X) 

+inf 
+inf 
inf 
+inf 
NaN 
NaN 
DIV
DIV(X, Y)
Description
Returns the result of integer division of X by Y. Division by zero returns
an error. Division by 1 may overflow. If
both inputs are NUMERIC
and the result is overflow,
then it returns a numeric overflow
error.
X  Y  DIV(X, Y) 

20  4  5 
12  7  1 
20  3  6 
0  20  0 
20  0  Error 
Return Data Type
The return data type is determined by the argument types with the following table.
INPUT  INT64  NUMERIC 

INT64  INT64  NUMERIC 
NUMERIC  NUMERIC  NUMERIC 
EXP
EXP(X)
Description
Computes e to the power of X, also called the natural exponential function. If the result underflows, this function returns a zero. Generates an error if the result overflows.
X  EXP(X) 

0.0  1.0 
+inf 
+inf 
inf 
0.0 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
FLOOR
FLOOR(X)
Description
Returns the largest integral value that is not greater than X.
X  FLOOR(X) 

2.0  2.0 
2.3  2.0 
2.8  2.0 
2.5  2.0 
2.3  3.0 
2.8  3.0 
2.5  3.0 
0  0 
+inf 
+inf 
inf 
inf 
NaN 
NaN 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
GREATEST
GREATEST(X1,...,XN)
Description
Returns the greatest value among X1,...,XN
. If any argument is NULL
, returns
NULL
. Otherwise, in the case of floatingpoint arguments, if any argument is
NaN
, returns NaN
. In all other cases, returns the value among X1,...,XN
that has the greatest value according to the ordering used by the ORDER BY
clause. The arguments X1, ..., XN
must be coercible to a common supertype, and
the supertype must support ordering.
X1,...,XN  GREATEST(X1,...,XN) 

3,5,1  5 
Return Data Types
Data type of the input values.
IEEE_DIVIDE
IEEE_DIVIDE(X, Y)
Description
Divides X by Y; this function never fails. Returns
FLOAT64
. Unlike the division operator (/),
this function does not generate errors for division by zero or overflow.
X  Y  IEEE_DIVIDE(X, Y) 

20.0  4.0  5.0 
0.0  25.0  0.0 
25.0  0.0  +inf 
25.0  0.0  inf 
0.0  0.0  NaN 
0.0  NaN 
NaN 
NaN 
0.0  NaN 
+inf 
+inf 
NaN 
inf 
inf 
NaN 
IS_INF
IS_INF(X)
Description
Returns TRUE
if the value is positive or negative infinity.
Returns FALSE
for NUMERIC
inputs since NUMERIC
cannot be INF
.
X  IS_INF(X) 

+inf 
TRUE 
inf 
TRUE 
25  FALSE 
IS_NAN
IS_NAN(X)
Description
Returns TRUE
if the value is a NaN
value.
Returns FALSE
for NUMERIC
inputs since
NUMERIC
cannot be NaN
.
X  IS_NAN(X) 

NaN 
TRUE 
25  FALSE 
LEAST
LEAST(X1,...,XN)
Description
Returns the least value among X1,...,XN
. If any argument is NULL
, returns
NULL
. Otherwise, in the case of floatingpoint arguments, if any argument is
NaN
, returns NaN
. In all other cases, returns the value among X1,...,XN
that has the least value according to the ordering used by the ORDER BY
clause. The arguments X1, ..., XN
must be coercible to a common supertype, and
the supertype must support ordering.
X1,...,XN  LEAST(X1,...,XN) 

3,5,1  1 
Return Data Types
Data type of the input values.
LN
LN(X)
Description
Computes the natural logarithm of X. Generates an error if X is less than or equal to zero.
X  LN(X) 

1.0  0.0 
+inf 
+inf 
X < 0 
Error 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
LOG
LOG(X [, Y])
Description
If only X is present, LOG
is a synonym of LN
. If Y is also present,
LOG
computes the logarithm of X to base Y.
X  Y  LOG(X, Y) 

100.0  10.0  2.0 
inf 
Any value  NaN 
Any value  +inf 
NaN 
+inf 
0.0 < Y < 1.0  inf 
+inf 
Y > 1.0  +inf 
X <= 0  Any value  Error 
Any value  Y <= 0  Error 
Any value  1.0  Error 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

INT64  FLOAT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
LOG10
LOG10(X)
Description
Similar to LOG
, but computes logarithm to base 10.
X  LOG10(X) 

100.0  2.0 
inf 
NaN 
+inf 
+inf 
X <= 0  Error 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
MOD
MOD(X, Y)
Description
Modulo function: returns the remainder of the division of X by Y. Returned value has the same sign as X. An error is generated if Y is 0.
X  Y  MOD(X, Y) 

25  12  1 
25  0  Error 
Return Data Type
The return data type is determined by the argument types with the following table.
INPUT  INT64  NUMERIC 

INT64  INT64  NUMERIC 
NUMERIC  NUMERIC  NUMERIC 
POW
POW(X, Y)
Description
Returns the value of X raised to the power of Y. If the result underflows and is not representable, then the function returns a value of zero.
X  Y  POW(X, Y) 

2.0  3.0  8.0 
1.0  Any value including NaN 
1.0 
Any value including NaN 
0  1.0 
1.0  +inf 
1.0 
1.0  inf 
1.0 
ABS(X) < 1  inf 
+inf 
ABS(X) > 1  inf 
0.0 
ABS(X) < 1  +inf 
0.0 
ABS(X) > 1  +inf 
+inf 
inf 
Y < 0  0.0 
inf 
Y > 0  inf if Y is an odd integer, +inf otherwise 
+inf 
Y < 0  0 
+inf 
Y > 0  +inf 
Finite value < 0  Noninteger  Error 
0  Finite value < 0  Error 
Return Data Type
The return data type is determined by the argument types with the following table.
INPUT  INT64  NUMERIC  FLOAT64 

INT64  FLOAT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
POWER
POWER(X, Y)
Description
Synonym of POW(X, Y)
.
ROUND
ROUND(X [, N])
Description
If only X is present, rounds X to the nearest integer. If N is present, rounds X to N decimal places after the decimal point. If N is negative, rounds off digits to the left of the decimal point. Rounds halfway cases away from zero. Generates an error if overflow occurs.
Expression  Return Value 

ROUND(2.0) 
2.0 
ROUND(2.3) 
2.0 
ROUND(2.8) 
3.0 
ROUND(2.5) 
3.0 
ROUND(2.3) 
2.0 
ROUND(2.8) 
3.0 
ROUND(2.5) 
3.0 
ROUND(0) 
0 
ROUND(+inf) 
+inf 
ROUND(inf) 
inf 
ROUND(NaN) 
NaN 
ROUND(123.7, 1) 
120.0 
ROUND(1.235, 2) 
1.24 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
SAFE_ADD
SAFE_ADD(X, Y)
Description
Equivalent to the addition operator (+
), but returns
NULL
if overflow occurs.
X  Y  SAFE_ADD(X, Y) 

5  4  9 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

INT64  INT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
SAFE_DIVIDE
SAFE_DIVIDE(X, Y)
Description
Equivalent to the division operator (X / Y
), but returns
NULL
if an error occurs, such as a division by zero error.
X  Y  SAFE_DIVIDE(X, Y) 

20  4  5 
0  20  0 
20  0  NULL 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

INT64  FLOAT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
SAFE_MULTIPLY
SAFE_MULTIPLY(X, Y)
Description
Equivalent to the multiplication operator (*
), but returns
NULL
if overflow occurs.
X  Y  SAFE_MULTIPLY(X, Y) 

20  4  80 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

INT64  INT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
SAFE_NEGATE
SAFE_NEGATE(X)
Description
Equivalent to the unary minus operator (
), but returns
NULL
if overflow occurs.
X  SAFE_NEGATE(X) 

+1  1 
1  +1 
0  0 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  INT64  NUMERIC  FLOAT64 
SAFE_SUBTRACT
SAFE_SUBTRACT(X, Y)
Description
Returns the result of Y subtracted from X.
Equivalent to the subtraction operator (
), but returns
NULL
if overflow occurs.
X  Y  SAFE_SUBTRACT(X, Y) 

5  4  1 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

INT64  INT64  NUMERIC  FLOAT64 
NUMERIC  NUMERIC  NUMERIC  FLOAT64 
FLOAT64  FLOAT64  FLOAT64  FLOAT64 
SIGN
SIGN(X)
Description
Returns 1
, 0
, or +1
for negative, zero and positive arguments
respectively. For floating point arguments, this function does not distinguish
between positive and negative zero.
X  SIGN(X) 

25  +1 
0  0 
25  1 
NaN  NaN 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  INT64  NUMERIC  FLOAT64 
SIN
SIN(X)
Description
Computes the sine of X where X is specified in radians. Never fails.
X  SIN(X) 

+inf 
NaN 
inf 
NaN 
NaN 
NaN 
SINH
SINH(X)
Description
Computes the hyperbolic sine of X where X is specified in radians. Generates an error if overflow occurs.
If X is NUMERIC
then, the output is FLOAT64
.
X  SINH(X) 

+inf 
+inf 
inf 
inf 
NaN 
NaN 
SQRT
SQRT(X)
Description
Computes the square root of X. Generates an error if X is less than 0.
X  SQRT(X) 

25.0 
5.0 
+inf 
+inf 
X < 0 
Error 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
TAN
TAN(X)
Description
Computes the tangent of X where X is specified in radians. Generates an error if overflow occurs.
X  TAN(X) 

+inf 
NaN 
inf 
NaN 
NaN 
NaN 
TANH
TANH(X)
Description
Computes the hyperbolic tangent of X where X is specified in radians. Does not fail.
If X is NUMERIC
then, the output is FLOAT64
.
X  TANH(X) 

+inf 
1.0 
inf 
1.0 
NaN 
NaN 
TRUNC
TRUNC(X [, N])
Description
If only X is present, TRUNC
rounds X to the nearest integer whose absolute
value is not greater than the absolute value of X. If N is also present, TRUNC
behaves like ROUND(X, N)
, but always rounds towards zero and never overflows.
X  TRUNC(X) 

2.0  2.0 
2.3  2.0 
2.8  2.0 
2.5  2.0 
2.3  2.0 
2.8  2.0 
2.5  2.0 
0  0 
+inf 
+inf 
inf 
inf 
NaN 
NaN 
Return Data Type
INPUT  INT64  NUMERIC  FLOAT64 

OUTPUT  FLOAT64  NUMERIC  FLOAT64 
Hash functions in GoogleSQL
GoogleSQL for Spanner supports the following hash functions.
Function list
Name  Summary 

FARM_FINGERPRINT

Computes the fingerprint of a STRING or
BYTES value, using the FarmHash Fingerprint64 algorithm.

SHA1

Computes the hash of a STRING or
BYTES value, using the SHA1 algorithm.

SHA256

Computes the hash of a STRING or
BYTES value, using the SHA256 algorithm.

SHA512

Computes the hash of a STRING or
BYTES value, using the SHA512 algorithm.

FARM_FINGERPRINT
FARM_FINGERPRINT(value)
Description
Computes the fingerprint of the STRING
or BYTES
input using the
Fingerprint64
function from the
opensource FarmHash library. The output
of this function for a particular input will never change.
Return type
INT64
Examples
WITH example AS (
SELECT 1 AS x, "foo" AS y, true AS z UNION ALL
SELECT 2 AS x, "apple" AS y, false AS z UNION ALL
SELECT 3 AS x, "" AS y, true AS z
)
SELECT
*,
FARM_FINGERPRINT(CONCAT(CAST(x AS STRING), y, CAST(z AS STRING)))
AS row_fingerprint
FROM example;
/*+++*
 x  y  z  row_fingerprint 
+++++
 1  foo  true  1541654101129638711 
 2  apple  false  2794438866806483259 
 3   true  4880158226897771312 
*+++*/
SHA1
SHA1(input)
Description
Computes the hash of the input using the
SHA1 algorithm. The input can either be
STRING
or BYTES
. The string version treats the input as an array of bytes.
This function returns 20 bytes.
Return type
BYTES
Example
SELECT SHA1("Hello World") as sha1;
 Note that the result of SHA1 is of type BYTES, displayed as a base64encoded string.
/**
 sha1 
++
 Ck1VqNd45QIvq3AZd8XYQLvEhtA= 
**/
SHA256
SHA256(input)
Description
Computes the hash of the input using the
SHA256 algorithm. The input can either be
STRING
or BYTES
. The string version treats the input as an array of bytes.
This function returns 32 bytes.
Return type
BYTES
Example
SELECT SHA256("Hello World") as sha256;
SHA512
SHA512(input)
Description
Computes the hash of the input using the
SHA512 algorithm. The input can either be
STRING
or BYTES
. The string version treats the input as an array of bytes.
This function returns 64 bytes.
Return type
BYTES
Example
SELECT SHA512("Hello World") as sha512;
String functions in GoogleSQL
GoogleSQL for Spanner supports string functions.
These string functions work on two different values:
STRING
and BYTES
data types. STRING
values must be wellformed UTF8.
Functions that return position values, such as STRPOS,
encode those positions as INT64
. The value 1
refers to the first character (or byte), 2
refers to the second, and so on.
The value 0
indicates an invalid position. When working on STRING
types, the
returned positions refer to character positions.
All string comparisons are done bytebybyte, without regard to Unicode canonical equivalence.
Function list
Name  Summary 

BYTE_LENGTH

Gets the number of BYTES in a STRING or
BYTES value.

CHAR_LENGTH

Gets the number of characters in a STRING value.

CHARACTER_LENGTH

Synonym for CHAR_LENGTH .

CODE_POINTS_TO_BYTES

Converts an array of extended ASCII code points to a
BYTES value.

CODE_POINTS_TO_STRING

Converts an array of extended ASCII code points to a
STRING value.

CONCAT

Concatenates one or more STRING or BYTES
values into a single result.

ENDS_WITH

Checks if a STRING or BYTES value is the suffix
of another value.

FORMAT

Formats data and produces the results as a STRING value.

FROM_BASE32

Converts a base32encoded STRING value into a
BYTES value.

FROM_BASE64

Converts a base64encoded STRING value into a
BYTES value.

FROM_HEX

Converts a hexadecimalencoded STRING value into a
BYTES value.

LENGTH

Gets the length of a STRING or BYTES value.

LOWER

Formats alphabetic characters in a STRING value as
lowercase.
Formats ASCII characters in a BYTES value as
lowercase.

LPAD

Prepends a STRING or BYTES value with a pattern.

LTRIM

Identical to the TRIM function, but only removes leading
characters.

NORMALIZE

Casesensitively normalizes the characters in a STRING value.

NORMALIZE_AND_CASEFOLD

Caseinsensitively normalizes the characters in a STRING value.

REGEXP_CONTAINS

Checks if a value is a partial match for a regular expression. 
REGEXP_EXTRACT

Produces a substring that matches a regular expression. 
REGEXP_EXTRACT_ALL

Produces an array of all substrings that match a regular expression. 
REGEXP_REPLACE

Produces a STRING value where all substrings that match a
regular expression are replaced with a specified value.

REPEAT

Produces a STRING or BYTES value that consists of
an original value, repeated.

REPLACE

Replaces all occurrences of a pattern with another pattern in a
STRING or BYTES value.

REVERSE

Reverses a STRING or BYTES value.

RPAD

Appends a STRING or BYTES value with a pattern.

RTRIM

Identical to the TRIM function, but only removes trailing
characters.

SAFE_CONVERT_BYTES_TO_STRING

Converts a BYTES value to a STRING value and
replace any invalid UTF8 characters with the Unicode replacement character,
U+FFFD .

SPLIT

Splits a STRING or BYTES value, using a delimiter.

STARTS_WITH

Checks if a STRING or BYTES value is a
prefix of another value.

STRPOS

Finds the position of the first occurrence of a subvalue inside another value. 
SUBSTR

Gets a portion of a STRING or BYTES value.

TO_BASE32

Converts a BYTES value to a
base32encoded STRING value.

TO_BASE64

Converts a BYTES value to a
base64encoded STRING value.

TO_CODE_POINTS

Converts a STRING or BYTES value into an array of
extended ASCII code points.

TO_HEX

Converts a BYTES value to a
hexadecimal STRING value.

TRIM

Removes the specified leading and trailing Unicode code points or bytes
from a STRING or BYTES value.

UPPER

Formats alphabetic characters in a STRING value as
uppercase.
Formats ASCII characters in a BYTES value as
uppercase.

BYTE_LENGTH
BYTE_LENGTH(value)
Description
Gets the number of BYTES
in a STRING
or BYTES
value,
regardless of whether the value is a STRING
or BYTES
type.
Return type
INT64
Examples
WITH example AS
(SELECT 'абвгд' AS characters, b'абвгд' AS bytes)
SELECT
characters,
BYTE_LENGTH(characters) AS string_example,
bytes,
BYTE_LENGTH(bytes) AS bytes_example
FROM example;
/*+++*
 characters  string_example  bytes  bytes_example 
+++++
 абвгд  10  абвгд  10 
*+++*/
CHAR_LENGTH
CHAR_LENGTH(value)
Description
Gets the number of characters in a STRING
value.
Return type
INT64
Examples
WITH example AS
(SELECT 'абвгд' AS characters)
SELECT
characters,
CHAR_LENGTH(characters) AS char_length_example
FROM example;
/*+*
 characters  char_length_example 
+++
 абвгд  5 
*+*/
CHARACTER_LENGTH
CHARACTER_LENGTH(value)
Description
Synonym for CHAR_LENGTH.
Return type
INT64
Examples
WITH example AS
(SELECT 'абвгд' AS characters)
SELECT
characters,
CHARACTER_LENGTH(characters) AS char_length_example
FROM example;
/*+*
 characters  char_length_example 
+++
 абвгд  5 
*+*/
CODE_POINTS_TO_BYTES
CODE_POINTS_TO_BYTES(ascii_code_points)
Description
Takes an array of extended ASCII
code points
as ARRAY<INT64>
and returns BYTES
.
To convert from BYTES
to an array of code points, see
TO_CODE_POINTS.
Return type
BYTES
Examples
The following is a basic example using CODE_POINTS_TO_BYTES
.
SELECT CODE_POINTS_TO_BYTES([65, 98, 67, 100]) AS bytes;
 Note that the result of CODE_POINTS_TO_BYTES is of type BYTES, displayed as a base64encoded string.
 In BYTES format, b'AbCd' is the result.
/**
 bytes 
++
 QWJDZA== 
**/
The following example uses a rotateby13 places (ROT13) algorithm to encode a string.
SELECT CODE_POINTS_TO_BYTES(ARRAY(
(SELECT
CASE
WHEN chr BETWEEN b'a' AND b'z'
THEN TO_CODE_POINTS(b'a')[offset(0)] +
MOD(code + 13  TO_CODE_POINTS(b'a')[offset(0)],26)
WHEN chr BETWEEN b'A' AND b'Z'
THEN TO_CODE_POINTS(b'A')[offset(0)] +
MOD(code + 13  TO_CODE_POINTS(b'A')[offset(0)],26)
ELSE code
END
FROM
(SELECT code, CODE_POINTS_TO_BYTES(ARRAY[code]) AS chr
FROM UNNEST(TO_CODE_POINTS(input)) AS code WITH OFFSET
ORDER BY OFFSET)
))) AS encoded_string
FROM UNNEST(ARRAY['Test String!']) AS input;
 Note that the result of CODE_POINTS_TO_BYTES is of type BYTES, displayed as a base64encoded string.
 In BYTES format, b'Grfg Fgevat!' is the result.
/**
 encoded_string 
++
 R3JmZyBGZ2V2YXQh 
**/
CODE_POINTS_TO_STRING
CODE_POINTS_TO_STRING(unicode_code_points)
Description
Takes an array of Unicode code points
as ARRAY<INT64>
and returns a STRING
.
To convert from a string to an array of code points, see TO_CODE_POINTS.
Return type
STRING
Examples
The following are basic examples using CODE_POINTS_TO_STRING
.
SELECT CODE_POINTS_TO_STRING([65, 255, 513, 1024]) AS string;
/**
 string 
++
 AÿȁЀ 
**/
SELECT CODE_POINTS_TO_STRING([97, 0, 0xF9B5]) AS string;
/**
 string 
++
 a例 
**/
SELECT CODE_POINTS_TO_STRING([65, 255, NULL, 1024]) AS string;
/**
 string 
++
 NULL 
**/
The following example computes the frequency of letters in a set of words.
WITH Words AS (
SELECT word
FROM UNNEST(['foo', 'bar', 'baz', 'giraffe', 'llama']) AS word
)
SELECT
CODE_POINTS_TO_STRING([code_point]) AS letter,
COUNT(*) AS letter_count
FROM Words,
UNNEST(TO_CODE_POINTS(word)) AS code_point
GROUP BY 1
ORDER BY 2 DESC;
/*+*
 letter  letter_count 
+++
 a  5 
 f  3 
 r  2 
 b  2 
 l  2 
 o  2 
 g  1 
 z  1 
 e  1 
 m  1 
 i  1 
*+*/
CONCAT
CONCAT(value1[, ...])
Description
Concatenates one or more STRING
or BYTE
values into a single result.
The function returns NULL
if any input argument is NULL
.
Return type
STRING
or BYTES
Examples
SELECT CONCAT('T.P.', ' ', 'Bar') as author;
/**
 author 
++
 T.P. Bar 
**/
With Employees AS
(SELECT
'John' AS first_name,
'Doe' AS last_name
UNION ALL
SELECT
'Jane' AS first_name,
'Smith' AS last_name
UNION ALL
SELECT
'Joe' AS first_name,
'Jackson' AS last_name)
SELECT
CONCAT(first_name, ' ', last_name)
AS full_name
FROM Employees;
/**
 full_name 
++
 John Doe 
 Jane Smith 
 Joe Jackson 
**/
ENDS_WITH
ENDS_WITH(value, suffix)
Desc