SHOW WARNINGS
SHOW WARNINGS
语句用于显示当前客户端连接中已执行语句的报错列表。与在 MySQL 中一样,sql_mode
极大地影响哪些语句会导致错误与警告。
语法图
ShowStmt:
ShowTargetFilterable:
示例
mysql> CREATE TABLE t1 (a INT UNSIGNED);
Query OK, 0 rows affected (0.11 sec)
mysql> INSERT INTO t1 VALUES (0);
Query OK, 1 row affected (0.02 sec)
mysql> SELECT 1/a FROM t1;
+------+
| 1/a |
+------+
| NULL |
+------+
row in set, 1 warning (0.00 sec)
mysql> SHOW WARNINGS;
+---------+------+---------------+
| Level | Code | Message |
+---------+------+---------------+
| Warning | 1365 | Division by 0 |
+---------+------+---------------+
row in set (0.00 sec)
mysql> INSERT INTO t1 VALUES (-1);
ERROR 1264 (22003): Out of range value for column 'a' at row 1
mysql> SELECT * FROM t1;
+------+
| a |
+------+
| 0 |
+------+
row in set (0.00 sec)
mysql> SET sql_mode='';
Query OK, 0 rows affected (0.00 sec)
mysql> INSERT INTO t1 VALUES (-1);
Query OK, 1 row affected, 1 warning (0.01 sec)
mysql> SHOW WARNINGS;
+---------+------+---------------------------+
| Level | Code | Message |
+---------+------+---------------------------+
| Warning | 1690 | constant -1 overflows int |
+---------+------+---------------------------+
row in set (0.00 sec)
mysql> SELECT * FROM t1;
+------+
| a |
+------+
| 0 |
| 0 |
+------+
rows in set (0.00 sec)
MySQL 兼容性
SHOW WARNINGS
语句与 MySQL 完全兼容。如有任何兼容性差异,请在 GitHub 上提交 issue。
另请参阅
- SHOW ERRORS
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