根據 MySQL 中的一個條件刪除表中部分行
我們首先建立一個表 -
mysql> create table DemoTable -> ( -> Id int, -> Name varchar(20) -> ); Query OK, 0 rows affected (0.60 sec)
使用 insert 命令在表中插入一些記錄
Insert some records in the table using insert command: mysql> insert into DemoTable values(100,'Bob'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(101,'Chris'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values(102,'David'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(103,'Sam'); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable values(104,'Carol'); Query OK, 1 row affected (0.10 sec)
使用 select 語句顯示錶中的所有記錄 -
mysql> select *from DemoTable;
這將產生以下輸出 -
+------+-------+ | Id | Name | +------+-------+ | 100 | Bob | | 101 | Chris | | 102 | David | | 103 | Sam | | 104 | Carol | +------+-------+ 5 rows in set (0.00 sec)
以下是僅從表中刪除有限行資料的查詢 -
mysql> delete from DemoTable -> where Id > 102; Query OK, 2 rows affected (0.10 sec)
讓我們再次檢查表記錄 -
mysql> select *from DemoTable;
這將產生以下輸出 -
+------+-------+ | Id | Name | +------+-------+ | 100 | Bob | | 101 | Chris | | 102 | David | +------+-------+ 3 rows in set (0.00 sec)
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