public final class Mutation implements Serializable
Represents an individual table modification to be applied to Cloud Spanner.
The types of mutation that can be created are defined by Op. To construct a mutation,
use one of the builder methods. For example, to create a mutation that will insert a value of "x"
into "C1" and a value of "y" into "C2" of table "T", write the following code:
Mutation m = Mutation.newInsertBuilder("T")
.set("C1").to("x")
.set("C2").to("y")
.build();
Mutations are applied to a database by performing a standalone write or buffering them as part of
a transaction. TODO(user): Add links/code samples once the corresponding APIs are available.
Mutation instances are immutable.
Static Methods
delete(String table, Key key)
public static Mutation delete(String table, Key key)
Returns a mutation that will delete the row with primary key key. Exactly equivalent to
delete(table, KeySet.singleKey(key)).
| Parameters |
| Name |
Description |
table |
String
|
key |
Key
|
delete(String table, KeySet keySet)
public static Mutation delete(String table, KeySet keySet)
Returns a mutation that will delete all rows with primary keys covered by keySet.
newInsertBuilder(String table)
public static Mutation.WriteBuilder newInsertBuilder(String table)
Returns a builder that can be used to construct an Op#INSERT mutation against
table; see the INSERT documentation for mutation semantics.
| Parameter |
| Name |
Description |
table |
String
|
newInsertOrUpdateBuilder(String table)
public static Mutation.WriteBuilder newInsertOrUpdateBuilder(String table)
Returns a builder that can be used to construct an Op#INSERT_OR_UPDATE mutation against
table; see the INSERT_OR_UPDATE documentation for mutation semantics.
| Parameter |
| Name |
Description |
table |
String
|
newReplaceBuilder(String table)
public static Mutation.WriteBuilder newReplaceBuilder(String table)
Returns a builder that can be used to construct an Op#REPLACE mutation against
table; see the REPLACE documentation for mutation semantics.
| Parameter |
| Name |
Description |
table |
String
|
newUpdateBuilder(String table)
public static Mutation.WriteBuilder newUpdateBuilder(String table)
Returns a builder that can be used to construct an Op#UPDATE mutation against
table; see the UPDATE documentation for mutation semantics.
| Parameter |
| Name |
Description |
table |
String
|
Methods
asMap()
public Map<String,Value> asMap()
For all types except Op#DELETE, constructs a map from column name to value. This is
mainly intended as a convenience for testing; direct access via #getColumns() and
#getValues() is more efficient.
equals(Object o)
public boolean equals(Object o)
| Parameter |
| Name |
Description |
o |
Object
|
Overrides
getColumns()
public Iterable<String> getColumns()
For all types except Op#DELETE, returns the columns that this mutation will affect.
getKeySet()
public KeySet getKeySet()
For Op#DELETE mutations, returns the key set that defines the rows to be deleted.
| Returns |
| Type |
Description |
KeySet |
|
getOperation()
public Mutation.Op getOperation()
Returns the type of operation that this mutation will perform.
getTable()
Returns the name of the table that this mutation will affect.
| Returns |
| Type |
Description |
String |
|
getValues()
public Iterable<Value> getValues()
For all types except Op#DELETE, returns the values that this mutation will write. The
number of elements returned is always the same as the number returned by #getColumns(),
and the ith value corresponds to the ith column.
hashCode()
| Returns |
| Type |
Description |
int |
|
Overrides
toString()
| Returns |
| Type |
Description |
String |
|
Overrides
