使用 DELETE 语句删除数据。

    示例如下：

    假设有如下所示数据的表 t1 和 t2：

    1. obclient> CREATE TABLE t1(c1 int primary key, c2 int);
    2. Query OK, 0 rows affected (0.16 sec)
    3. obclient> SELECT * FROM t1;
    4. +----+------+
    5. | c1 | c2   |
    6. +----+------+
    7. |  1 |    1 |
    8. |  2 |    2 |
    9. |  3 |    3 |
    10. |  4 |    4 |
    11. +----+------+
    12. 4 rows in set (0.06 sec)
    14. obclient> CREATE TABLE t2(c1 int primary key, c2 int) partition BY key(c1) partitions 4;
    15. Query OK, 0 rows affected (0.19 sec)
    16. obclient> SELECT * FROM t2;
    17. +----+------+
    18. | c1 | c2   |
    19. +----+------+
    20. |  5 |    5 |
    21. |  1 |    1 |
    22. |  2 |    2 |
    23. |  3 |    3 |
    24. +----+------+
    25. 4 rows in set (0.02 sec)

    • 单表删除，删除“c1=2”的行，其中 c1 列为表 t1 中的 Primary Key。

      1. obclient> DELETE FROM t1 WHERE c1 = 2;
      2. Query OK, 1 row affected (0.02 sec)
      4. obclient> SELECT * FROM t1;
      5. +----+------+
      6. | c1 | c2   |
      7. +----+------+
      8. |  1 |    1 |
      9. |  3 |    3 |
      10. |  4 |    4 |
      11. +----+------+
      12. 3 rows in set (0.01 sec)

    • 单表删除，删除表 t2 中按照 c2 列排序之后的第一行数据。

      1. obclient> DELETE FROM t1 ORDER BY c2 LIMIT 1;
      2. Query OK, 1 row affected (0.01 sec)
      4. obclient> SELECT * FROM t1;
      5. +----+------+
      6. | c1 | c2   |
      7. +----+------+
      8. |  2 |    2 |
      9. |  3 |    3 |
      10. |  4 |    4 |
      11. +----+------+
      12. 3 rows in set (0.00 sec)

    • 单表删除，删除表 t2 的 p2 分区的数据。

      1. obclient> DELETE FROM t2 PARTITION(p2);
      2. Query OK, 3 rows affected (0.02 sec)
      4. obclient> SELECT * FROM t2;
      5. +----+------+
      6. | c1 | c2   |
      7. +----+------+
      8. |  5 |    5 |
      9. +----+------+
      10. 1 row in set (0.02 sec)

    • 多表删除，删除 t1、t2 表中 “t1.c1 = t2.c1” 的数据。

      1. obclient> DELETE t1, t2 FROM t1, t2 WHERE t1.c1 = t2.c1;
      2. Query OK, 3 rows affected (0.02 sec)
      4. obclient> SELECT * FROM t1;
      5. +----+------+
      6. | c1 | c2   |
      7. +----+------+
      8. |  4 |    4 |
      9. +----+------+
      10. 1 row in set (0.01 sec)
      12. obclient> SELECT * FROM t2;
      13. +----+------+
      14. | c1 | c2   |
      15. +----+------+
      16. |  5 |    5 |
      17. +----+------+
      18. 1 row in set (0.01 sec)

    • 多表删除，删除 t1、t2 表中 “t1.c1 = t2.c1” 的数据。

      1. obclient> DELETE FROM t1, t2 USING t1, t2 WHERE t1.c1 = t2.c1;
      2. Query OK, 4 rows affected (0.02 sec)
      4. obclient> SELECT * FROM t1;
      5. +----+------+
      6. | c1 | c2   |
      7. +----+------+
      8. |  4 |    4 |
      9. +----+------+
      10. 1 row in set (0.01 sec)
      12. obclient> SELECT * FROM t2;
      13. Empty set (0.01 sec)

    更多 DELETE 语句相关的语法说明请参见 DELETE。