MySQL中数据表的增操作

今天学习到表的增操作，写个博客总结一下，PS:以下所有的凝视都是我在电脑上所有操作完毕后，再拷贝到记事本上加入的。至于在运行的时候可不能够那样加入凝视，就有待考证了。

选择库

mysql> show databases;#查看眼下有哪些数据库存在
+--------------------+
| Database           |
+--------------------+
| information_schema |
| ceshi_ku           |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> use ceshi_ku;#选择该数据库，等下用来建表，貌似选择数据库能够不要"；"
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed

建表

mysql> create table biao
    -> (
    -> id int,
    -> name char(10),
    -> gender char(2),
    -> gongsi char(15),
    -> gongzi float
    -> );#先建立一个简单的表，编号、名字、性别、公司、工资，建表眼下不是重点，是方便接下来的操作
Query OK, 0 rows affected (0.13 sec)

mysql> select * from biao;#查看表中的内容，眼下是空表
Empty set (0.00 sec)

插入数据（所有列，多行）

mysql> insert into biao#选择要插入哪张表
    -> (id,name,gender,gongsi,gongzi)#往哪些列里面插入内容
    -> values#接下来開始插入3条，分别用","隔开，最后一个用";"
    -> (1,'ma yun','n','tao bao',6000.5),#把要插入内容依次写好，不可调换顺序！要一一相应
    -> (2,'xiao hong','v','xin lang',5000.7),
    -> (3,'xiao ming','n','bai du',3000.4);
Query OK, 3 rows affected (0.08 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> select * from biao;#查看表中的内容，如今会发现多了3行
+------+-----------+--------+----------+--------+
| 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 |
+------+-----------+--------+----------+--------+
3 rows in set (0.01 sec)

插入数据（缺省列，单行）

mysql> insert into biao#这次没有指定往哪些列里面插入，没指定就是往全部列插入
    -> values
    -> (4,'li si','n','sou hu',9000.2);#这次是仅仅插入一行，也能够插入多行，仅仅需用","隔开
Query OK, 1 row affected (0.07 sec)

mysql> select * from biao;#查看表内容，会发现比上次多了一行
+------+-----------+--------+----------+--------+
| 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 |
+------+-----------+--------+----------+--------+
4 rows in set (0.00 sec)

插入数据（指定列，多行）

mysql> insert into biao
    -> (id,name,gongsi,gongzi)#这次不是往全部列插入，而是部分列
    -> values
    -> (5,'lao wang','wang yi',1000.5),#依次写好便可，记得相应关系，
    -> (6,'xiao li','ku gou',700.1);
Query OK, 2 rows affected (0.15 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> select * from biao;#查看表内容，这次会上次发现多了2行，可是"gender"是空的
+------+-----------+--------+----------+--------+
| 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)