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This section describes functions and operators for examining
and manipulating bit strings, that is values of the types
`bit`

and ```
bit
varying
```

. Aside from the usual comparison operators, the
operators shown in Table 9.13
can be used. Bit string operands of `&`

, `|`

, and
`#`

must be of equal length. When bit
shifting, the original length of the string is preserved, as
shown in the examples.

**Table 9.13. Bit String
Operators**

Operator | Description | Example | Result |
---|---|---|---|

`||` |
concatenation | ```
B'10001' ||
B'011'
``` |
`10001011` |

`&` |
bitwise AND | ```
B'10001' &
B'01101'
``` |
`00001` |

`|` |
bitwise OR | ```
B'10001' |
B'01101'
``` |
`11101` |

`#` |
bitwise XOR | ```
B'10001' #
B'01101'
``` |
`11100` |

`~` |
bitwise NOT | `~ B'10001'` |
`01110` |

`<<` |
bitwise shift left | ```
B'10001' <<
3
``` |
`01000` |

`>>` |
bitwise shift right | ```
B'10001' >>
2
``` |
`00100` |

The following SQL-standard
functions work on bit strings as well as character strings:

, `length`

,
`bit_length`

, `octet_length`

,
`position`

, `substring`

.`overlay`

The following functions work on bit strings as well as binary
strings:

, `get_bit`

. When
working with a bit string, these functions number the first
(leftmost) bit of the string as bit 0.`set_bit`

In addition, it is possible to cast integral values to and
from type `bit`

. Some examples:

44::bit(10)000010110044::bit(3)100cast(-44 as bit(12))111111010100'1110'::bit(4)::integer14

Note that casting to just “bit” means casting to `bit(1)`

, and so will deliver only the least
significant bit of the integer.

Casting an integer to `bit(n)`

copies the rightmost `n`

bits.
Casting an integer to a bit string width wider than the integer
itself will sign-extend on the left.

If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.