JSON.STRAPPEND - Amazon MemoryDB
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

JSON.STRAPPEND

Append a string to the JSON strings at the path.

Syntax

JSON.STRAPPEND <key> [path] <json_string>

  • key (required) – key of JSON document type

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

  • json_string (required) – JSON representation of a string. Note that a JSON string must be quoted, i.e., '"foo"'.

Return

If the path is enhanced syntax:

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

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

  • SYNTAXERR error if the input json argument is not a valid JSON string.

  • NONEXISTENT error if the path does not exist.

If the path is restricted syntax:

  • Integer, the string's new length.

  • If multiple string values are selected, the command returns the new length of the last updated string.

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

  • WRONGTYPE error if the input json argument is not a valid JSON string.

  • NONEXISTENT error if the path 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.STRAPPEND k1 $.a.a '"a"'
1) (integer) 2
127.0.0.1:6379> JSON.STRAPPEND k1 $.a.* '"a"'
1) (integer) 3
127.0.0.1:6379> JSON.STRAPPEND k1 $.b.* '"a"'
1) (integer) 2
2) (nil)
127.0.0.1:6379> JSON.STRAPPEND k1 $.c.* '"a"'
1) (integer) 2
2) (integer) 3
127.0.0.1:6379> JSON.STRAPPEND k1 $.c.b '"a"'
1) (integer) 4
127.0.0.1:6379> JSON.STRAPPEND k1 $.d.* '"a"'
1) (nil)
2) (integer) 2
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.STRAPPEND k1 .a.a '"a"'
(integer) 2
127.0.0.1:6379> JSON.STRAPPEND k1 .a.* '"a"'
(integer) 3
127.0.0.1:6379> JSON.STRAPPEND k1 .b.* '"a"'
(integer) 2
127.0.0.1:6379> JSON.STRAPPEND k1 .c.* '"a"'
(integer) 3
127.0.0.1:6379> JSON.STRAPPEND k1 .c.b '"a"'
(integer) 4
127.0.0.1:6379> JSON.STRAPPEND k1 .d.* '"a"'
(integer) 2