Gets the length of the array values at the path.
Syntax
JSON.ARRLEN <key> [path]
key (required) – A Valkey or Redis OSS 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 that represent the array length at each path.
-
If a value is not an array, its corresponding return value is null.
Null if the document key does not exist.
If the path is restricted syntax:
Integer, array length.
If multiple objects are selected, the command returns the first array's length.
-
WRONGTYPEerror if the value at the path is not an array. -
NONEXISTENT JSONerror 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", "b"], ["a", "b", "c"]]' OK 127.0.0.1:6379> JSON.ARRLEN k1 $[*] 1) (integer) 0 2) (integer) 1 3) (integer) 2 4) (integer) 3 127.0.0.1:6379> JSON.SET k2 . '[[], "a", ["a", "b"], ["a", "b", "c"], 4]' OK 127.0.0.1:6379> JSON.ARRLEN k2 $[*] 1) (integer) 0 2) (nil) 3) (integer) 2 4) (integer) 3 5) (nil)
Restricted path syntax:
127.0.0.1:6379> JSON.SET k1 . '[[], ["a"], ["a", "b"], ["a", "b", "c"]]' OK 127.0.0.1:6379> JSON.ARRLEN k1 [*] (integer) 0 127.0.0.1:6379> JSON.ARRLEN k1 [1] (integer) 1 127.0.0.1:6379> JSON.ARRLEN k1 [2] (integer) 2 127.0.0.1:6379> JSON.SET k2 . '[[], "a", ["a", "b"], ["a", "b", "c"], 4]' OK 127.0.0.1:6379> JSON.ARRLEN k2 [1] (error) WRONGTYPE JSON element is not an array 127.0.0.1:6379> JSON.ARRLEN k2 [0] (integer) 0 127.0.0.1:6379> JSON.ARRLEN k2 [6] (error) OUTOFBOUNDARIES Array index is out of bounds 127.0.0.1:6379> JSON.ARRLEN k2 a.b (error) NONEXISTENT JSON path does not exist
