JSON.STRLEN - Amazon MemoryDB for Redis
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JSON.STRLEN

Get lengths of the JSON string values at the path.

Syntax

JSON.STRLEN <key> [path]

  • key (required) – Redis key of JSON document type

  • path (optional) – a JSON path. Defaults to the root if not provided

Return

If the path is enhanced syntax:

  • Array of integers, representing the length of string value at each path.

  • If a value is not a string, its corresponding return value is null.

  • Null if the document key does not exist.

If the path is restricted syntax:

  • Integer, the string's length.

  • If multiple string values are selected, the command returns the first string's length.

  • WRONGTYPE error if the value at the path is not a string.

  • NONEXISTENT error if the path does not exist.

  • Null if the document key does not exist.

Examples

Enhanced path syntax:

127.0.0.1:6379> JSON.SET k1 $ '{"a":{"a":"a"}, "b":{"a":"a", "b":1}, "c":{"a":"a", "b":"bb"}, "d":{"a":1, "b":"b", "c":3}}'
OK
127.0.0.1:6379> JSON.STRLEN k1 $.a.a
1) (integer) 1
127.0.0.1:6379> JSON.STRLEN k1 $.a.*
1) (integer) 1
127.0.0.1:6379> JSON.STRLEN k1 $.c.*
1) (integer) 1
2) (integer) 2
127.0.0.1:6379> JSON.STRLEN k1 $.c.b
1) (integer) 2
127.0.0.1:6379> JSON.STRLEN k1 $.d.*
1) (nil)
2) (integer) 1
3) (nil)

Restricted path syntax:

127.0.0.1:6379> JSON.SET k1 $ '{"a":{"a":"a"}, "b":{"a":"a", "b":1}, "c":{"a":"a", "b":"bb"}, "d":{"a":1, "b":"b", "c":3}}'
OK
127.0.0.1:6379> JSON.STRLEN k1 .a.a
(integer) 1
127.0.0.1:6379> JSON.STRLEN k1 .a.*
(integer) 1
127.0.0.1:6379> JSON.STRLEN k1 .c.*
(integer) 1
127.0.0.1:6379> JSON.STRLEN k1 .c.b
(integer) 2
127.0.0.1:6379> JSON.STRLEN k1 .d.*
(integer) 1