SQL基础(二)

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创建表：

mysql> create table t_person(    -> fname varchar(20),    -> fage int,    -> fremark varchar(20),    -> primary key(fname)    -> );Query OK, 0 rows affectedmysql> create table t_debt(    -> fnumber varchar(20),    -> famount decimal(10,2) not null,    -> fperson varchar(20),    -> primary key(fnumber)    -> ,foreign key(fperson) references t_person(fname)    -> );Query OK, 0 rows affectedmysql> show tables;+--------------------+| Tables_in_learnsql |+--------------------+| t_debt             || t_person           |+--------------------+2 rows in set

插入数据：

mysql> insert into t_person(fname,fage,fremark) values('Tom',18,'USA');Query OK, 1 row affected

查看表数据：

mysql> select * from t_person;+-------+------+---------+| fname | fage | fremark |+-------+------+---------+| Tom   |   18 | USA     |+-------+------+---------+1 row in set

插入多行表数据：

mysql> insert into t_person(fname,fage,fremark) values('Jim',20,'USA');Query OK, 1 row affectedmysql> insert into t_person(fname,fage,fremark) values('Lili',22,'China');Query OK, 1 row affectedmysql> insert into t_person(fname,fage,fremark) values('XiaoWang',17,'China');Query OK, 1 row affectedmysql> select * from t_person;+----------+------+---------+| fname    | fage | fremark |+----------+------+---------+| Jim      |   20 | USA     || Lili     |   22 | China   || Tom      |   18 | USA     || XiaoWang |   17 | China   |+----------+------+---------+4 rows in set

插入表数据的其它方式：

mysql> insert into t_person(fage,fname,fremark) values(21,'Kimi','Korea');Query OK, 1 row affectedmysql> select * from t_person;+----------+------+---------+| fname    | fage | fremark |+----------+------+---------+| Jim      |   20 | USA     || Kimi     |   21 | Korea   || Lili     |   22 | China   || Tom      |   18 | USA     || XiaoWang |   17 | China   |+----------+------+---------+5 rows in setmysql> insert into t_person(fage,fname) values(22,'LXF');Query OK, 1 row affectedmysql> select * from t_person;+----------+------+---------+| fname    | fage | fremark |+----------+------+---------+| Jim      |   20 | USA     || Kimi     |   21 | Korea   || Lili     |   22 | China   || LXF      |   22 | NULL    || Tom      |   18 | USA     || XiaoWang |   17 | China   |+----------+------+---------+6 rows in setmysql> insert into t_person values('Iurenl',23,'China');Query OK, 1 row affectedmysql> select * from t_person;+----------+------+---------+| fname    | fage | fremark |+----------+------+---------+| Iurenl   |   23 | China   || Jim      |   20 | USA     || Kimi     |   21 | Korea   || Lili     |   22 | China   || LXF      |   22 | NULL    || Tom      |   18 | USA     || XiaoWang |   17 | China   |+----------+------+---------+7 rows in set

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