KEYS

KEYS pattern

Available since:

Redis Open Source 1.0.0

Time complexity:

O(N) with N being the number of keys in the database, under the assumption that the key names in the database and the given pattern have limited length.

ACL categories:

@keyspace, @read, @slow, @dangerous,

Returns all keys matching pattern.

While the time complexity for this operation is O(N), the constant times are fairly low. For example, Redis running on an entry level laptop can scan a 1 million key database in 40 milliseconds.

Warning: consider KEYS as a command that should only be used in production environments with extreme care. It may ruin performance when it is executed against large databases. This command is intended for debugging and special operations, such as changing your keyspace layout. Don't use KEYS in your regular application code. If you're looking for a way to find keys in a subset of your keyspace, consider using SCAN or sets.

Supported glob-style patterns:

• h?llo matches hello, hallo and hxllo
• h*llo matches hllo and heeeello
• h[ae]llo matches hello and hallo, but not hillo
• h[^e]llo matches hallo, hbllo, ... but not hello
• h[a-b]llo matches hallo and hbllo

Use \ to escape special characters if you want to match them verbatim.

When using Redis Cluster, the search is optimized for patterns that imply a single slot. If a pattern can only match keys of one slot, Redis only iterates over keys in that slot, rather than the whole database, when searching for keys matching the pattern. For example, with the pattern {a}h*llo, Redis would only try to match it with the keys in slot 15495, which hash tag {a} implies. To use pattern with hash tag, see Hash tags in the Cluster specification for more information.

Examples

Return information