Bitwise
bit_count()
bit_count(x, bits)
→ bigint
Count the number of bits set in x (treated as bits-bit signed integer) in 2’s complement representation:
SELECT bit_count(9, 64); -- 2
SELECT bit_count(9, 8); -- 2
SELECT bit_count(-7, 64); -- 62
SELECT bit_count(-7, 8); -- 6
bitwise_and()
bitwise_and(x, y)
→ bigint
Returns the bitwise AND of x and y in 2’s complement representation.
Bitwise AND of 19 (binary: 10011) and 25 (binary: 11001) results in 17 (binary: 10001):
SELECT bitwise_and(19,25); -- 17
bitwise_not(x)
→ bigint
Returns the bitwise NOT of x in 2’s complement representation (NOT x = -x - 1):
SELECT bitwise_not(-12); -- 11
SELECT bitwise_not(19); -- -20
SELECT bitwise_not(25); -- -26
bitwise_or()
bitwise_or(x, y)
→ bigint
Returns the bitwise OR of x and y in 2’s complement representation.
Bitwise OR of 19 (binary: 10011) and 25 (binary: 11001) results in 27 (binary: 11011):
SELECT bitwise_or(19,25); -- 27
bitwise_xor()
bitwise_xor(x, y)
→ bigint
Returns the bitwise XOR of x and y in 2’s complement representation.
Bitwise XOR of 19 (binary: 10011) and 25 (binary: 11001) results in 10 (binary: 01010):
SELECT bitwise_xor(19,25); -- 10
bitwise_left_shift()
bitwise_left_shift(value, shift)
→ [same as value]
Returns the left shifted value of value.
Shifting 1 (binary: 001) by two bits results in 4 (binary: 00100):
SELECT bitwise_left_shift(1, 2); -- 4
Shifting 5 (binary: 0101) by two bits results in 20 (binary: 010100):
SELECT bitwise_left_shift(5, 2); -- 20
Shifting a value by 0 always results in the original value:
SELECT bitwise_left_shift(20, 0); -- 20
SELECT bitwise_left_shift(42, 0); -- 42
Shifting 0 by a shift always results in 0:
SELECT bitwise_left_shift(0, 1); -- 0
SELECT bitwise_left_shift(0, 2); -- 0
bitwise_right_shift()
bitwise_right_shift(value, shift)
→ [same as value]
Returns the logical right shifted value of value.
Shifting 8 (binary: 1000) by three bits results in 1 (binary: 001):
SELECT bitwise_right_shift(8, 3); -- 1
Shifting 9 (binary: 1001) by one bit results in 4 (binary: 100):
SELECT bitwise_right_shift(9, 1); -- 4
Shifting a value by 0 always results in the original value:
SELECT bitwise_right_shift(20, 0); -- 20
SELECT bitwise_right_shift(42, 0); -- 42
Shifting a value by 64 or more bits results in 0:
SELECT bitwise_right_shift( 12, 64); -- 0
SELECT bitwise_right_shift(-45, 64); -- 0
Shifting 0 by a shift always results in 0:
SELECT bitwise_right_shift(0, 1); -- 0
SELECT bitwise_right_shift(0, 2); -- 0
bitwise_right_shift_arithmetic()
bitwise_right_shift_arithmetic(value, shift)
→ [same as value]
Returns the arithmetic right shifted value of value.
Returns the same values as bitwise_right_shift() when shifting by less than 64 bits. Shifting by 64 or more bits results in 0 for a positive and -1 for a negative value:
SELECT bitwise_right_shift_arithmetic( 12, 64); -- 0
SELECT bitwise_right_shift_arithmetic(-45, 64); -- -1
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