JSON_EXTRACT_BOOL
Description
JSON_EXTRACT_BOOL extracts the field specified by <json_path> from a JSON object and converts it to BOOLEAN type.
Syntax
JSON_EXTRACT_BOOL(<json_object>, <json_path>)
Parameters
<json_object>: JSON type, the target parameter to extract from.<json_path>: String type, the JSON path to extract the target element from the target JSON.
Return Value
Nullable(BOOLEAN) Returns the extracted BOOLEAN value, returns NULL in some cases
Usage Notes
- If
<json_object>or<json_path>is NULL, returns NULL. - If the element specified by
<json_path>does not exist, returns NULL. - If the element specified by
<json_path>cannot be converted to BOOLEAN, returns NULL. - Its behavior is consistent with "cast + json_extract", which is equivalent to:
CAST(JSON_EXTRACT(<json_object>, <json_path>) as BOOLEAN)
Examples
- Normal parameters
SELECT json_extract_bool('{"id": true, "name": "doris"}', '$.id');+------------------------------------------------------------+| json_extract_bool('{"id": true, "name": "doris"}', '$.id') |+------------------------------------------------------------+| 1 |+------------------------------------------------------------+
- Case where path does not exist
SELECT json_extract_bool('{"id": true, "name": "doris"}', '$.id2');+-------------------------------------------------------------+| json_extract_bool('{"id": true, "name": "doris"}', '$.id2') |+-------------------------------------------------------------+| NULL |+-------------------------------------------------------------+
- NULL parameters
SELECT json_extract_bool('{"id": true, "name": "doris"}', NULl);+----------------------------------------------------------+| json_extract_bool('{"id": true, "name": "doris"}', NULl) |+----------------------------------------------------------+| NULL |+----------------------------------------------------------+SELECT json_extract_bool(NULL, '$.id2');+----------------------------------+| json_extract_bool(NULL, '$.id2') |+----------------------------------+| NULL |+----------------------------------+
- Case where conversion to BOOLEAN is not possible
SELECT json_extract_bool('{"id": 123, "name": "doris"}','$.name');+------------------------------------------------------------+| json_extract_bool('{"id": 123, "name": "doris"}','$.name') |+------------------------------------------------------------+| NULL |+------------------------------------------------------------+