今天學習到表的增操作,寫個博客總結一下,PS:下面所有的註釋都是我在電腦上全部操作完成後,再複製到記事本上添加的。至於在執行的時候可不可以那樣添加註釋,就有待考證了。
選擇庫
mysql> show databases;#查看目前有哪些數據庫存在
+--------------------+
| Database |
+--------------------+
| information_schema |
| ceshi_ku |
| mysql |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)
mysql> use ceshi_ku;#選擇該數據庫,等下用來建表,貌似選擇數據庫可以不要";"
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
-> );#先建立一個簡單的表,編號、名字、性別、公司、工資,建表目前不是重點,是方便接下來的操作
Query OK, 0 rows affected (0.13 sec)
mysql> select * from biao;#查看錶中的內容,目前是空表
Empty set (0.00 sec)
插入數據(全部列,多行)
mysql> insert into biao#選擇要插入哪張表
-> (id,name,gender,gongsi,gongzi)#往哪些列裏面插入內容
-> values#接下來開始插入3條,分別用","隔開,最後一個用";"
-> (1,'ma yun','n','tao bao',6000.5),#把要插入內容依次寫好,不可調換順序!要一一對應
-> (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;#查看錶中的內容,現在會發現多了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)
插入數據(缺省列,單行)
mysql> insert into biao#這次沒有指定往哪些列裏面插入,沒指定就是往所有列插入
-> values
-> (4,'li si','n','sou hu',9000.2);#這次是隻插入一行,也可以插入多行,只需用","隔開
Query OK, 1 row affected (0.07 sec)
mysql> select * from biao;#查看錶內容,會發現比上次多了一行
+------+-----------+--------+----------+--------+
| 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)
插入數據(指定列,多行)
mysql> insert into biao
-> (id,name,gongsi,gongzi)#這次不是往所有列插入,而是部分列
-> values
-> (5,'lao wang','wang yi',1000.5),#依次寫好便可,記得對應關係,
-> (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;#查看錶內容,這次會上次發現多了2行,但是"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)