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BITOP

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BITOP AND destkey key [key ...]
BITOP OR destkey key [key ...]
BITOP XOR destkey key [key ...]
BITOP NOT destkey key
BITOP DIFF destkey key key [key ...]
BITOP DIFF1 destkey key key [key ...]
BITOP ANDOR destkey key key [key ...]
BITOP ONE destkey key [key ...]
Group
Bitmap
Complexity
O(N) where N is the length of the longest input string
Arity
-4 (at least 4 words, counting the command name)
Flags
write, slow
Keys
first 2, last final argument, step 1
HotKV Cloud
All plans
On-Premise
no license needed

BITOP combines the strings at the source keys bit by bit and stores the result at destkey, replacing whatever was there. Shorter inputs are treated as if padded with zero bytes to the length of the longest one, and a missing source counts as an empty string. NOT takes exactly one source and inverts every bit. If the result is empty (all sources missing or empty), destkey is deleted.

In a cluster, all keys must hash to the same slot.

Options

Section titled “Options”
Operation Result bit
AND 1 when the bit is 1 in every source
OR 1 when the bit is 1 in at least one source
XOR 1 when the bit is 1 in an odd number of sources
NOT The inverse of the single source’s bit
DIFF 1 when the bit is 1 in the first source and 0 in every other source
DIFF1 1 when the bit is 1 in at least one of the other sources and 0 in the first
ANDOR 1 when the bit is 1 in the first source and in at least one of the other sources
ONE 1 when the bit is 1 in exactly one source

DIFF, DIFF1 and ANDOR need at least two source keys. ONE accepts one or more. The operation name is not case-sensitive.

Return value

Section titled “Return value”
Case RESP2 RESP3
Always Integer: the length in bytes of the stored result Integer

Errors:

  • ERR BITOP NOT must be called with a single source key.
  • ERR BITOP DIFF must be called with at least two source keys. (and the same for DIFF1 and ANDOR).
  • ERR syntax error for an unknown operation.
  • WRONGTYPE when a source key holds a value that is not a string.

Examples

Section titled “Examples”
127.0.0.1:6379> SET a "\xf0"
OK
127.0.0.1:6379> SET b "\x0f\x01"
OK
127.0.0.1:6379> BITOP OR both a b
(integer) 2
127.0.0.1:6379> GET both
"\xff\x01"
127.0.0.1:6379> BITOP AND common a b
(integer) 2
127.0.0.1:6379> GET common
"\x00\x00"
127.0.0.1:6379> BITOP NOT inv a
(integer) 1
127.0.0.1:6379> GET inv
"\x0f"

The four operations added in Redis 8.2 compare the first source with the others. With x = 11110000, y = 00111100 and z = 00001111:

127.0.0.1:6379> SET x "\xf0"
OK
127.0.0.1:6379> SET y "\x3c"
OK
127.0.0.1:6379> SET z "\x0f"
OK
127.0.0.1:6379> BITOP DIFF only_x x y z
(integer) 1
127.0.0.1:6379> GET only_x
"\xc0"
127.0.0.1:6379> BITOP DIFF1 not_x x y z
(integer) 1
127.0.0.1:6379> GET not_x
"\x0f"
127.0.0.1:6379> BITOP ANDOR x_and_other x y z
(integer) 1
127.0.0.1:6379> GET x_and_other
"0"
127.0.0.1:6379> BITOP ONE exactly_one x y z
(integer) 1
127.0.0.1:6379> GET exactly_one
"\xc3"

Compatibility

Section titled “Compatibility”

Same as Redis 8.2, including the DIFF, DIFF1, ANDOR and ONE operations.

See also

Section titled “See also”

BITCOUNT, SETBIT, BITFIELD