| Did you know ... | Search Documentation: |
 | Pack logtalk -- logtalk-3.98.0/docs/apis/_sources/redis_0.rst.txt |
- HOME
- DOWNLOAD
- DOCUMENTATION
- TUTORIALS
- Beginner▶
- Advanced▶
- Web applications▶
- Semantic web▶
- Graphics▶
- Machine learning▶
- External collections▶
- For packagers▶
- COMMUNITY
- COMMERCIAL
- WIKI
.. index:: single: redis .. _redis/0:
.. rst-class:: right
object
redis
Redis client library with support for strings, keys, hashes, lists, sets, and sorted sets. Inspired by Sean Charles GNU Prolog Redis client.
| Availability:
| logtalk_load(redis(loader))
| Author: Paulo Moura | Version: 0:7:0 | Date: 2026-02-10
| Compilation flags:
| static, context_switching_calls
| Provides: | :ref:`logtalk::message_tokens//2 <logtalk/0::message_tokens//2>` | Uses: | :ref:`list <list/0>` | :ref:`logtalk <logtalk/0>` | :ref:`socket <socket/0>`
| Remarks:
- Command representation: Use the Redis command name as the functor of a compound term where the arguments are the command arguments.
- Valid arguments: Atoms, integers, and floats. Always use atoms instead of double-quoted "strings". This helps portability by not depending on the value of the
double_quotesflag. - Wrapper predicates: The library provides convenient wrapper predicates for common Redis operations. For operations without a wrapper, use the generic send/3 predicate.
| Inherited public predicates: | (none)
.. contents:: :local: :backlinks: top
Public predicates
.. index:: connect/1 .. _redis/0::connect/1:
connect/1 ^^^^^^^^^^^^^
Connect to a Redis server running on localhost using the default 6379 port.
| Compilation flags:
| static
| Template:
| connect(Connection)
| Mode and number of proofs:
| connect(--ground) - one
.. index:: connect/3 .. _redis/0::connect/3:
connect/3 ^^^^^^^^^^^^^
Connect to a Redis server running on the given host and port.
| Compilation flags:
| static
| Template:
| connect(Host,Port,Connection)
| Mode and number of proofs:
| connect(+atom,+integer,--ground) - one
.. index:: disconnect/1 .. _redis/0::disconnect/1:
disconnect/1 ^^^^^^^^^^^^^^^^
Disconnect from a Redis server.
| Compilation flags:
| static
| Template:
| disconnect(Connection)
| Mode and number of proofs:
| disconnect(++ground) - one
.. index:: send/3 .. _redis/0::send/3:
send/3 ^^^^^^^^^^
Sends a request to the a Redis server and returns its reply.
| Compilation flags:
| static
| Template:
| send(Connection,Request,Reply)
| Mode and number of proofs:
| send(++ground,++callable,--callable) - one
.. index:: console/1 .. _redis/0::console/1:
console/1 ^^^^^^^^^^^^^
Sends a request to a Redis server running on localhost at the default 6379 port and prints the reply.
| Compilation flags:
| static
| Template:
| console(Request)
| Mode and number of proofs:
| console(++callable) - one
.. index:: get/3 .. _redis/0::get/3:
get/3 ^^^^^^^^^
Gets the value of a key.
| Compilation flags:
| static
| Template:
| get(Connection,Key,Value)
| Mode and number of proofs:
| get(+ground,+atom,-atom) - one
.. index:: set/4 .. _redis/0::set/4:
set/4 ^^^^^^^^^
Sets the value of a key.
| Compilation flags:
| static
| Template:
| set(Connection,Key,Value,Status)
| Mode and number of proofs:
| set(+ground,+atom,+ground,-atom) - one
.. index:: append/4 .. _redis/0::append/4:
append/4 ^^^^^^^^^^^^
Appends a value to a key. Returns the length of the string after the append.
| Compilation flags:
| static
| Template:
| append(Connection,Key,Value,Length)
| Mode and number of proofs:
| append(+ground,+atom,+ground,-integer) - one
.. index:: getrange/5 .. _redis/0::getrange/5:
getrange/5 ^^^^^^^^^^^^^^
Gets a substring of the string stored at a key.
| Compilation flags:
| static
| Template:
| getrange(Connection,Key,Start,End,Substring)
| Mode and number of proofs:
| getrange(+ground,+atom,+integer,+integer,-atom) - one
.. index:: setrange/5 .. _redis/0::setrange/5:
setrange/5 ^^^^^^^^^^^^^^
Overwrites part of a string at a key starting at the specified offset. Returns the length of the string after modification.
| Compilation flags:
| static
| Template:
| setrange(Connection,Key,Offset,Value,Length)
| Mode and number of proofs:
| setrange(+ground,+atom,+integer,+ground,-integer) - one
.. index:: strlen/3 .. _redis/0::strlen/3:
strlen/3 ^^^^^^^^^^^^
Gets the length of the value stored at a key.
| Compilation flags:
| static
| Template:
| strlen(Connection,Key,Length)
| Mode and number of proofs:
| strlen(+ground,+atom,-integer) - one
.. index:: mget/3 .. _redis/0::mget/3:
mget/3 ^^^^^^^^^^
Gets the values of multiple keys. Returns a list of values.
| Compilation flags:
| static
| Template:
| mget(Connection,Keys,Values)
| Mode and number of proofs:
| mget(+ground,+list(atom),-list) - one
.. index:: mset/3 .. _redis/0::mset/3:
mset/3 ^^^^^^^^^^
Sets multiple key-value pairs. Pairs should be provided as a flat list [Key1, Value1, Key2, Value2, ...].
| Compilation flags:
| static
| Template:
| mset(Connection,Pairs,Status)
| Mode and number of proofs:
| mset(+ground,+list,-atom) - one
.. index:: incr/3 .. _redis/0::incr/3:
incr/3 ^^^^^^^^^^
Increments the integer value of a key by one. Returns the value after increment.
| Compilation flags:
| static
| Template:
| incr(Connection,Key,Value)
| Mode and number of proofs:
| incr(+ground,+atom,-integer) - one
.. index:: decr/3 .. _redis/0::decr/3:
decr/3 ^^^^^^^^^^
Decrements the integer value of a key by one. Returns the value after decrement.
| Compilation flags:
| static
| Template:
| decr(Connection,Key,Value)
| Mode and number of proofs:
| decr(+ground,+atom,-integer) - one
.. index:: incrby/4 .. _redis/0::incrby/4:
incrby/4 ^^^^^^^^^^^^
Increments the integer value of a key by the specified amount. Returns the value after increment.
| Compilation flags:
| static
| Template:
| incrby(Connection,Key,Increment,Value)
| Mode and number of proofs:
| incrby(+ground,+atom,+integer,-integer) - one
.. index:: decrby/4 .. _redis/0::decrby/4:
decrby/4 ^^^^^^^^^^^^
Decrements the integer value of a key by the specified amount. Returns the value after decrement.
| Compilation flags:
| static
| Template:
| decrby(Connection,Key,Decrement,Value)
| Mode and number of proofs:
| decrby(+ground,+atom,+integer,-integer) - one
.. index:: del/3 .. _redis/0::del/3:
del/3 ^^^^^^^^^
Deletes a key. Returns the number of keys removed.
| Compilation flags:
| static
| Template:
| del(Connection,Key,Count)
| Mode and number of proofs:
| del(+ground,+atom,-integer) - one
.. index:: exists/3 .. _redis/0::exists/3:
exists/3 ^^^^^^^^^^^^
Checks if a key exists. Returns 1 if the key exists, 0 otherwise.
| Compilation flags:
| static
| Template:
| exists(Connection,Key,Exists)
| Mode and number of proofs:
| exists(+ground,+atom,-integer) - one
.. index:: keys/3 .. _redis/0::keys/3:
keys/3 ^^^^^^^^^^
Finds all keys matching a pattern. Returns a list of keys.
| Compilation flags:
| static
| Template:
| keys(Connection,Pattern,Keys)
| Mode and number of proofs:
| keys(+ground,+atom,-list) - one
.. index:: ttl/3 .. _redis/0::ttl/3:
ttl/3 ^^^^^^^^^
Gets the time to live for a key in seconds. Returns -1 if the key has no expiry, -2 if the key does not exist.
| Compilation flags:
| static
| Template:
| ttl(Connection,Key,Seconds)
| Mode and number of proofs:
| ttl(+ground,+atom,-integer) - one
.. index:: expire/4 .. _redis/0::expire/4:
expire/4 ^^^^^^^^^^^^
Sets a timeout on a key in seconds. Returns 1 if the timeout was set, 0 if the key does not exist.
| Compilation flags:
| static
| Template:
| expire(Connection,Key,Seconds,Result)
| Mode and number of proofs:
| expire(+ground,+atom,+integer,-integer) - one
.. index:: persist/3 .. _redis/0::persist/3:
persist/3 ^^^^^^^^^^^^^
Removes the expiration from a key. Returns 1 if the timeout was removed, 0 if the key does not exist or has no timeout.
| Compilation flags:
| static
| Template:
| persist(Connection,Key,Result)
| Mode and number of proofs:
| persist(+ground,+atom,-integer) - one
.. index:: rename/4 .. _redis/0::rename/4:
rename/4 ^^^^^^^^^^^^
Renames a key. Returns status OK or error if the key does not exist.
| Compilation flags:
| static
| Template:
| rename(Connection,OldKey,NewKey,Status)
| Mode and number of proofs:
| rename(+ground,+atom,+atom,-atom) - one
.. index:: type/3 .. _redis/0::type/3:
type/3 ^^^^^^^^^^
Gets the type of the value stored at a key. Returns one of: string, list, set, zset, hash, stream, none.
| Compilation flags:
| static
| Template:
| type(Connection,Key,Type)
| Mode and number of proofs:
| type(+ground,+atom,-atom) - one
.. index:: hset/5 .. _redis/0::hset/5:
hset/5 ^^^^^^^^^^
Sets a field in a hash. Returns 1 if a new field was created, 0 if the field was updated.
| Compilation flags:
| static
| Template:
| hset(Connection,Key,Field,Value,Result)
| Mode and number of proofs:
| hset(+ground,+atom,+atom,+ground,-integer) - one
.. index:: hget/4 .. _redis/0::hget/4:
hget/4 ^^^^^^^^^^
Gets the value of a field in a hash.
| Compilation flags:
| static
| Template:
| hget(Connection,Key,Field,Value)
| Mode and number of proofs:
| hget(+ground,+atom,+atom,-ground) - one
.. index:: hgetall/3 .. _redis/0::hgetall/3:
hgetall/3 ^^^^^^^^^^^^^
Gets all fields and values in a hash. Returns a flat list of alternating fields and values.
| Compilation flags:
| static
| Template:
| hgetall(Connection,Key,FieldsValues)
| Mode and number of proofs:
| hgetall(+ground,+atom,-list) - one
.. index:: hdel/4 .. _redis/0::hdel/4:
hdel/4 ^^^^^^^^^^
Deletes a field from a hash. Returns the number of fields removed.
| Compilation flags:
| static
| Template:
| hdel(Connection,Key,Field,Count)
| Mode and number of proofs:
| hdel(+ground,+atom,+atom,-integer) - one
.. index:: hexists/4 .. _redis/0::hexists/4:
hexists/4 ^^^^^^^^^^^^^
Checks if a field exists in a hash. Returns 1 if the field exists, 0 otherwise.
| Compilation flags:
| static
| Template:
| hexists(Connection,Key,Field,Exists)
| Mode and number of proofs:
| hexists(+ground,+atom,+atom,-integer) - one
.. index:: hkeys/3 .. _redis/0::hkeys/3:
hkeys/3 ^^^^^^^^^^^
Gets all field names in a hash.
| Compilation flags:
| static
| Template:
| hkeys(Connection,Key,Fields)
| Mode and number of proofs:
| hkeys(+ground,+atom,-list) - one
.. index:: hvals/3 .. _redis/0::hvals/3:
hvals/3 ^^^^^^^^^^^
Gets all values in a hash.
| Compilation flags:
| static
| Template:
| hvals(Connection,Key,Values)
| Mode and number of proofs:
| hvals(+ground,+atom,-list) - one
.. index:: hlen/3 .. _redis/0::hlen/3:
hlen/3 ^^^^^^^^^^
Gets the number of fields in a hash.
| Compilation flags:
| static
| Template:
| hlen(Connection,Key,Count)
| Mode and number of proofs:
| hlen(+ground,+atom,-integer) - one
.. index:: lpush/4 .. _redis/0::lpush/4:
lpush/4 ^^^^^^^^^^^
Prepends a value to a list. Returns the length of the list after the push.
| Compilation flags:
| static
| Template:
| lpush(Connection,Key,Value,Length)
| Mode and number of proofs:
| lpush(+ground,+atom,+ground,-integer) - one
.. index:: rpush/4 .. _redis/0::rpush/4:
rpush/4 ^^^^^^^^^^^
Appends a value to a list. Returns the length of the list after the push.
| Compilation flags:
| static
| Template:
| rpush(Connection,Key,Value,Length)
| Mode and number of proofs:
| rpush(+ground,+atom,+ground,-integer) - one
.. index:: lpop/3 .. _redis/0::lpop/3:
lpop/3 ^^^^^^^^^^
Removes and returns the first element of a list.
| Compilation flags:
| static
| Template:
| lpop(Connection,Key,Value)
| Mode and number of proofs:
| lpop(+ground,+atom,-ground) - one
.. index:: rpop/3 .. _redis/0::rpop/3:
rpop/3 ^^^^^^^^^^
Removes and returns the last element of a list.
| Compilation flags:
| static
| Template:
| rpop(Connection,Key,Value)
| Mode and number of proofs:
| rpop(+ground,+atom,-ground) - one
.. index:: lrange/5 .. _redis/0::lrange/5:
lrange/5 ^^^^^^^^^^^^
Gets a range of elements from a list. Indices are zero-based.
| Compilation flags:
| static
| Template:
| lrange(Connection,Key,Start,Stop,Elements)
| Mode and number of proofs:
| lrange(+ground,+atom,+integer,+integer,-list) - one
.. index:: llen/3 .. _redis/0::llen/3:
llen/3 ^^^^^^^^^^
Gets the length of a list.
| Compilation flags:
| static
| Template:
| llen(Connection,Key,Length)
| Mode and number of proofs:
| llen(+ground,+atom,-integer) - one
.. index:: lrem/5 .. _redis/0::lrem/5:
lrem/5 ^^^^^^^^^^
Removes elements from a list. Count > 0: remove from head, Count < 0: remove from tail, Count = 0: remove all. Returns the number of removed elements.
| Compilation flags:
| static
| Template:
| lrem(Connection,Key,Count,Value,Removed)
| Mode and number of proofs:
| lrem(+ground,+atom,+integer,+ground,-integer) - one
.. index:: ltrim/5 .. _redis/0::ltrim/5:
ltrim/5 ^^^^^^^^^^^
Trims a list to the specified range.
| Compilation flags:
| static
| Template:
| ltrim(Connection,Key,Start,Stop,Status)
| Mode and number of proofs:
| ltrim(+ground,+atom,+integer,+integer,-atom) - one
.. index:: sadd/4 .. _redis/0::sadd/4:
sadd/4 ^^^^^^^^^^
Adds a member to a set. Returns the number of elements added.
| Compilation flags:
| static
| Template:
| sadd(Connection,Key,Member,Count)
| Mode and number of proofs:
| sadd(+ground,+atom,+ground,-integer) - one
.. index:: srem/4 .. _redis/0::srem/4:
srem/4 ^^^^^^^^^^
Removes a member from a set. Returns the number of elements removed.
| Compilation flags:
| static
| Template:
| srem(Connection,Key,Member,Count)
| Mode and number of proofs:
| srem(+ground,+atom,+ground,-integer) - one
.. index:: smembers/3 .. _redis/0::smembers/3:
smembers/3 ^^^^^^^^^^^^^^
Gets all members in a set.
| Compilation flags:
| static
| Template:
| smembers(Connection,Key,Members)
| Mode and number of proofs:
| smembers(+ground,+atom,-list) - one
.. index:: sismember/4 .. _redis/0::sismember/4:
sismember/4 ^^^^^^^^^^^^^^^
Checks if a value is a member of a set. Returns 1 if the member exists, 0 otherwise.
| Compilation flags:
| static
| Template:
| sismember(Connection,Key,Member,IsMember)
| Mode and number of proofs:
| sismember(+ground,+atom,+ground,-integer) - one
.. index:: scard/3 .. _redis/0::scard/3:
scard/3 ^^^^^^^^^^^
Gets the number of members in a set.
| Compilation flags:
| static
| Template:
| scard(Connection,Key,Count)
| Mode and number of proofs:
| scard(+ground,+atom,-integer) - one
.. index:: zadd/5 .. _redis/0::zadd/5:
zadd/5 ^^^^^^^^^^
Adds a member with a score to a sorted set. Returns the number of elements added.
| Compilation flags:
| static
| Template:
| zadd(Connection,Key,Score,Member,Count)
| Mode and number of proofs:
| zadd(+ground,+atom,+number,+ground,-integer) - one
.. index:: zrem/4 .. _redis/0::zrem/4:
zrem/4 ^^^^^^^^^^
Removes a member from a sorted set. Returns the number of elements removed.
| Compilation flags:
| static
| Template:
| zrem(Connection,Key,Member,Count)
| Mode and number of proofs:
| zrem(+ground,+atom,+ground,-integer) - one
.. index:: zrange/5 .. _redis/0::zrange/5:
zrange/5 ^^^^^^^^^^^^
Gets a range of members from a sorted set, ordered from lowest to highest score.
| Compilation flags:
| static
| Template:
| zrange(Connection,Key,Start,Stop,Members)
| Mode and number of proofs:
| zrange(+ground,+atom,+integer,+integer,-list) - one
.. index:: zrank/4 .. _redis/0::zrank/4:
zrank/4 ^^^^^^^^^^^
Gets the rank (index) of a member in a sorted set, ordered from lowest to highest score. Returns nil if the member does not exist.
| Compilation flags:
| static
| Template:
| zrank(Connection,Key,Member,Rank)
| Mode and number of proofs:
| zrank(+ground,+atom,+ground,-integer) - one
.. index:: zcard/3 .. _redis/0::zcard/3:
zcard/3 ^^^^^^^^^^^
Gets the number of members in a sorted set.
| Compilation flags:
| static
| Template:
| zcard(Connection,Key,Count)
| Mode and number of proofs:
| zcard(+ground,+atom,-integer) - one
.. index:: zscore/4 .. _redis/0::zscore/4:
zscore/4 ^^^^^^^^^^^^
Gets the score of a member in a sorted set.
| Compilation flags:
| static
| Template:
| zscore(Connection,Key,Member,Score)
| Mode and number of proofs:
| zscore(+ground,+atom,+ground,-ground) - one
Protected predicates
(no local declarations; see entity ancestors if any)
Private predicates
(no local declarations; see entity ancestors if any)
Operators
(none)