Nayuta Yanagisawa (Inactive) added a comment - 2021-08-05 03:26 holyfoot FYI, the patch for MDEV-24523 ( MariaDB/server/pull/1841 ) also fixes the present issue, but the patch only applied to 10.3 or later. MariaDB [(none)]> SELECT JSON_REPLACE( '{"a":"b"}' , '$.*' , 'c' ); + -------------------------------------+ | JSON_REPLACE( '{"a":"b"}' , '$.*' , 'c' ) | + -------------------------------------+ | NULL | + -------------------------------------+ 1 row in set , 1 warning (0.001 sec)   MariaDB [(none)]> show warnings; + ---------+------+-----------------------------------------------------------------------------+ | Level | Code | Message | + ---------+------+-----------------------------------------------------------------------------+ | Warning | 4044 | Wildcards in JSON path not allowed in argument 2 to function 'json_replace' | + ---------+------+-----------------------------------------------------------------------------+ 1 row in set (0.000 sec)