根据 MySQL 中的条件从表中删除某些行
mysqlmysqli database
首先我们创建一个表 −
mysql> create table DemoTable -> ( -> Id int, -> Name varchar(20) -> ); Query OK, 0 rows affected (0.60 sec)
使用 insert 在表中插入一些记录 command:
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 语句显示表中的所有记录 −
mysql> select *from DemoTable;
这将产生以下输出 −
+------+-------+ | Id | Name | +------+-------+ | 100 | Bob | | 101 | Chris | | 102 | David | | 103 | Sam | | 104 | Carol | +------+-------+ 5 rows in set (0.00 sec)
以下是从表中删除有限行的查询 −
mysql> delete from DemoTable -> where Id > 102; Query OK, 2 rows affected (0.10 sec)
让我们再次检查表记录 −
mysql> select *from DemoTable;
这将产生以下输出 −
+------+-------+ | Id | Name | +------+-------+ | 100 | Bob | | 101 | Chris | | 102 | David | +------+-------+ 3 rows in set (0.00 sec)
