Bit Functions in Standard SQL

BigQuery supports the following bit functions.

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     |
+-------+--------+---------------------------------------------+--------+
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