JSON_LENGTH
Overview
Returns the number of elements in a JSON array, or the number of keys in a JSON object. For scalar values (numbers, strings, null), returns 1.
Syntax
JSON_LENGTH(<json>)
Parameters
<json>: JSON type, the source data. Strings must first be converted using PARSE_JSON.
Examples
-- Array: returns the number of elements
SELECT json_length(PARSE_JSON('[1,2,3]'));
-- 3
-- Object: returns the number of keys
SELECT json_length(PARSE_JSON('{"a":1,"b":2}'));
-- 2
-- Scalar value returns 1
SELECT json_length(PARSE_JSON('null'));
-- 1
