Error number: 3012; Symbol: ER_EXPLAIN_NOT_SUPPORTED; SQLSTATE: HY000
Message: EXPLAIN FOR CONNECTION command is supported only for SELECT/UPDATE/INSERT/DELETE/REPLACE
:
错误说明:
ER_EXPLAIN_NOT_SUPPORTED 错误指示MySQL不支持 EXPLAIN 命令。
在MySQL终端运行EXPLAIN语句时可能会出现此错误:
mysql> EXPLAIN SELECT * FROM Table;
ERROR 3012 (HY000): EXPLAIN not supported
解决方法:
在MySQL 5.7和更高版本中,EXPLAIN语句必须加入EXPLAIN FORMAT = JSON参数才能正确工作。因此,正确的语句格式是:
mysql> EXPLAIN FORMAT=JSON SELECT * FROM Table;