BIT_XOR

Takes the bitwise XOR of all non-null input values. If the input parameter is NULL, the return value is also NULL.

Behavior Type

Immutable

Syntax

BIT_XOR ( expression )

Parameters

expression

The BINARY or VARBINARY input value to evaluate. BIT_XOR operates on VARBINARY types explicitly and on BINARY types implicitly through casts.

Returns

BIT_XOR returns:

The same value as the argument data type.
1 for each bit compared, if there are an odd number of arguments with set bits; otherwise 0.

If the columns are different lengths, the return values are treated as though they are all equal in length and are right-extended with zero bytes. For example, given a group containing hex values ff, null, and f, the function ignores the null value and extends the value f to f0.

Example

First create a sample table and projections with binary columns:

The example that follows uses table t with a single column of VARBINARY data type:

=> CREATE TABLE t ( c VARBINARY(2) );
=> INSERT INTO t values(HEX_TO_BINARY('0xFF00')); 
=> INSERT INTO t values(HEX_TO_BINARY('0xFFFF'));
=> INSERT INTO t values(HEX_TO_BINARY('0xF00F'));

Query table t to see column c output:

=> SELECT TO_HEX(c) FROM t;
 TO_HEX
--------
 ff00
 ffff
 f00f
(3 rows)

Query table t to get the XOR value for column c:

=> SELECT TO_HEX(BIT_XOR(c)) FROM t;
 TO_HEX
--------
 f0f0
(1 row)