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:

ShowStmt

ShowTargetFilterable:

ShowTargetFilterable

示例

  1. mysql> CREATE TABLE t1 (a INT UNSIGNED);
  2. Query OK, 0 rows affected (0.11 sec)
  4. mysql> INSERT INTO t1 VALUES (0);
  5. Query OK, 1 row affected (0.02 sec)
  7. mysql> SELECT 1/a FROM t1;
  8. +------+
  9. | 1/a  |
  10. +------+
  11. | NULL |
  12. +------+
  13. 1 row in set, 1 warning (0.00 sec)
  15. mysql> SHOW WARNINGS;
  16. +---------+------+---------------+
  17. | Level   | Code | Message       |
  18. +---------+------+---------------+
  19. | Warning | 1365 | Division by 0 |
  20. +---------+------+---------------+
  21. 1 row in set (0.00 sec)
  23. mysql> INSERT INTO t1 VALUES (-1);
  24. ERROR 1264 (22003): Out of range value for column 'a' at row 1
  25. mysql> SELECT * FROM t1;
  26. +------+
  27. | a    |
  28. +------+
  29. |    0 |
  30. +------+
  31. 1 row in set (0.00 sec)
  33. mysql> SET sql_mode='';
  34. Query OK, 0 rows affected (0.00 sec)
  36. mysql> INSERT INTO t1 VALUES (-1);
  37. Query OK, 1 row affected, 1 warning (0.01 sec)
  39. mysql> SHOW WARNINGS;
  40. +---------+------+---------------------------+
  41. | Level   | Code | Message                   |
  42. +---------+------+---------------------------+
  43. | Warning | 1690 | constant -1 overflows int |
  44. +---------+------+---------------------------+
  45. 1 row in set (0.00 sec)
  47. mysql> SELECT * FROM t1;
  48. +------+
  49. | a    |
  50. +------+
  51. |    0 |
  52. |    0 |
  53. +------+
  54. 2 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