MySQL中数据表的查操作_MySQL

mysql> show tables;#查看当前数据库下的所有表+--------------------+| Tables_in_ceshi_ku |+--------------------+| biao || ceshi_biao |+--------------------+2 rows in set (0.00 sec)mysql> select * from biao;#查看该表所有的内容，*代表通配符，在这里是代表所有的列+------+-----------+--------+----------+--------+| id | name| gender | gongsi | gongzi |+------+-----------+--------+----------+--------+|1 | ma yun| n| tao bao| 6000.5 ||2 | xiao hong | v| xin lang | 5000.7 ||3 | xiao ming | n| bai du | 3000.4 ||4 | li si | n| sou hu | 9000.2 ||5 | lao wang| NULL | wang yi| 1000.5 ||6 | xiao li | NULL | ku gou |700.1 |+------+-----------+--------+----------+--------+6 rows in set (0.00 sec)

mysql> select * from biao where id>4;#查询所有列，部分行，即id大于4的行+------+----------+--------+---------+--------+| id | name | gender | gongsi| gongzi |+------+----------+--------+---------+--------+|5 | lao wang | NULL | wang yi | 1000.5 ||6 | xiao li| NULL | ku gou|700.1 |+------+----------+--------+---------+--------+2 rows in set (0.02 sec)

mysql> select name,gongzi from biao;#查询部分列，即"name"和"gongzi"列，之间用","隔开。选择所有行+-----------+--------+| name| gongzi |+-----------+--------+| ma yun| 6000.5 || xiao hong | 5000.7 || xiao ming | 3000.4 || li si | 9000.2 || lao wang| 1000.5 || xiao li |700.1 |+-----------+--------+6 rows in set (0.02 sec)

mysql> select name from biao where gongzi>3000;#选择部分列，即"name"列，也可以多个列。然后选择工资>3000的行+-----------+| name|+-----------+| ma yun|| xiao hong || xiao ming || li si |+-----------+4 rows in set (0.00 sec)