Commandsscan
SCAN
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Look up keys in batches
Usage: scan cursor.
KEYS scans and returns all keys at once, while SCAN returns about 10 keys at a time.
When there are many keys, KEYS takes a long time and cannot process other commands in the meantime. SCAN was introduced as an alternative.
If there are many keys, specify the next cursor and look them up repeatedly. When all keys have been returned, the next cursor is 0.
SSCAN, ZSCAN, and HSCAN look up members of a key, while SCAN looks up all keys in the DB.
Example
| Command> | scan 0 |
| Result> | next cursor -> 1024 0) key001 1) key002 2) key005 ... 11) key021 |
| Command> | scan 1024 |
| Result> | next cursor -> 18944 0) key031 1) key022 2) key035 ... 9) key151 |
Using the MATCH key_pattern option
Usage: scan cursor MATCH pattern.
Looks up only keys that match the specified key_pattern.
This is a glob-style pattern.
Example
| Command> | scan 0 match key* |
| Result> | next cursor -> 1024 0) key001 1) key002 2) key005 ... 11) key021 |
Using the COUNT count option
Usage: scan cursor COUNT 10.
The number of keys returned is not always exactly the specified count. Redis adjusts the count considering processing time.
Example
| Command> | scan 0 count 10 |
| Result> | next cursor -> 1024 0) key001 1) key002 2) key005 ... 11) key021 |
Using the TYPE type option
Usage: scan cursor TYPE string.
If TYPE is specified, only keys of that type are returned.
Example
| Command> | scan 0 type string |
| Result> | next cursor -> 1024 0) key001 1) key002 2) key005 ... 11) key021 |
Syntax
SCAN cursor [MATCH pattern] [COUNT count] [TYPE type]
- Available since version 2.8.0.
The TYPE option is available since Redis 6.0.0. - Time complexity is O(N).
| Related commands | KEYS, SSCAN, ZSCAN, HSCAN |
| Clients for Java | Jedis, Lettuce, Redisson | Clients for C | Hiredis |
| << RM | SCAN | SORT >> |
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