Forward Xu created CALCITE-2892: ----------------------------------- Summary: Add the JSON_KEYS function Key: CALCITE-2892 URL: https://issues.apache.org/jira/browse/CALCITE-2892 Project: Calcite Issue Type: New Feature Reporter: Forward Xu
[{{JSON_KEYS(_{{json_doc}}_[, _{{path}}_])}}|https://dev.mysql.com/doc/refman/5.7/en/json-search-functions.html#function_json-keys] Returns the keys from the top-level value of a JSON object as a JSON array, or, if a _{{path}}_ argument is given, the top-level keys from the selected path. Returns {{NULL}} if any argument is {{NULL}}, the _{{json_doc}}_ argument is not an object, or _{{path}}_, if given, does not locate an object. An error occurs if the _{{json_doc}}_argument is not a valid JSON document or the _{{path}}_ argument is not a valid path expression or contains a {{*}} or {{**}} wildcard. The result array is empty if the selected object is empty. If the top-level value has nested subobjects, the return value does not include keys from those subobjects. Example SQL: {code:java} // code placeholder SELECT JSON_KEYS(v) AS c1 ,JSON_KEYS(v, 'lax $.a') AS c2 ,JSON_KEYS(v, '$.b') AS c3 ,JSON_KEYS(v, 'strict $.a[0]') AS c4 ,JSON_KEYS(v, 'strict $.a[1]') AS c5 FROM (VALUES ('{"a": [10, true],"b": {"c": 30}}')) AS t(v) LIMIT 10; {code} Result: ||c1||c2||c3||c4||c5|| |["a", "b"]|[NULL]|["c"]|[NULL]|[NULL]| -- This message was sent by Atlassian JIRA (v7.6.3#76005)