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12.12. Bit Functions

Table 12.16. Bitwise Functions

Name	Description
`BIT_COUNT()`	Return the number of bits that are set
`&`	Bitwise AND
`~`	Invert bits
`\|`	Bitwise OR
`^`	Bitwise XOR
`<<`	Left shift
`>>`	Right shift

MySQL uses BIGINT (64-bit) arithmetic for bit operations, so these operators have a maximum range of 64 bits.

|

Bitwise OR:
```
mysql> SELECT 29 | 15;        -> 31
```
The result is an unsigned 64-bit integer.

Bitwise AND:

mysql> SELECT 29 &
                    15;        -> 13

The result is an unsigned 64-bit integer.

Bitwise XOR:

mysql> SELECT 1 ^ 1;        -> 0mysql> SELECT 1 ^ 0;        -> 1mysql> SELECT 11 ^ 3;        -> 8

The result is an unsigned 64-bit integer.

<<

Shifts a longlong (BIGINT) number to the left.
```
mysql> SELECT 1 <<
                    2;        -> 4
```
The result is an unsigned 64-bit integer. The value is truncated to 64 bits. In particular, if the shift count is greater or equal to the width of an unsigned 64-bit number, the result is zero.
>>

Shifts a longlong (BIGINT) number to the right.
```
mysql> SELECT 4 >>
                    2;        -> 1
```
The result is an unsigned 64-bit integer. The value is truncated to 64 bits. In particular, if the shift count is greater or equal to the width of an unsigned 64-bit number, the result is zero.
~

Invert all bits.
```
mysql> SELECT 5 & ~1;        -> 4
```
The result is an unsigned 64-bit integer.

Returns the number of bits that are set in the argument N.

mysql> SELECT BIT_COUNT(29),
                    BIT_COUNT(b'101010');        -> 4, 3

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