MySQL学习笔记.插入，更新，删除数据

首先创建一个名为student的表

mysql> CREATE TABLE STUDENT(
    -> ID INT PRIMARY KEY AUTO_INCREMENT,
    -> NAME CHAR(40) NOT NULL,
    -> AGE INT NOT NULL,
    -> GRADE DOUBLE
    -> );
Query OK, 0 rows affected (0.11 sec)

mysql> DESC STUDENT;
+-------+----------+------+-----+---------+----------------+
| Field | Type     | Null | Key | Default | Extra          |
+-------+----------+------+-----+---------+----------------+
| ID    | int(11)  | NO   | PRI | NULL    | auto_increment |
| NAME  | char(40) | NO   |     | NULL    |                |
| AGE   | int(11)  | NO   |     | NULL    |                |
| GRADE | double   | YES  |     | NULL    |                |
+-------+----------+------+-----+---------+----------------+
4 rows in set (0.00 sec)

插入数据

1. 插入一条数据

mysql> INSERT INTO STUDENT VALUES(1,'LUNA',20,80);
Query OK, 1 row affected (0.05 sec)

mysql> SELECT * FROM STUDENT;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  1 | LUNA |  20 |    80 |
+----+------+-----+-------+
1 row in set (0.00 sec)

2. 插入多条数据

mysql> INSERT INTO STUDENT(NAME,AGE,GRADE) VALUES('LUNA',20,80),('NANA',21,85),('TOM',19,88);
Query OK, 3 rows affected (0.06 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM STUDENT;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  1 | LUNA |  20 |    80 |
|  2 | LUNA |  20 |    80 |
|  3 | NANA |  21 |    85 |
|  4 | TOM  |  19 |    88 |
+----+------+-----+-------+
4 rows in set (0.00 sec)

3. 将另一个表中数据插入到表中

创建一个student_new的表，结构与student一样。

mysql> CREATE TABLE STUDENT_NEW(
    -> ID INT PRIMARY KEY AUTO_INCREMENT,
    -> NAME CHAR(40) NOT NULL,
    -> AGE INT NOT NULL,
    -> GRADE DOUBLE
    -> );
Query OK, 0 rows affected (0.11 sec)

mysql> INSERT INTO STUDENT_NEW VALUES(5,'BOBO',22,88);
Query OK, 1 row affected (0.06 sec)

mysql> INSERT INTO STUDENT_NEW VALUES(6,'BOBY',22,98);
Query OK, 1 row affected (0.05 sec)

mysql> SELECT * FROM STUDENT_NEW;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  5 | BOBO |  22 |    88 |
|  6 | BOBY |  22 |    98 |
+----+------+-----+-------+
2 rows in set (0.00 sec)

插入

mysql> INSERT INTO STUDENT(ID,NAME,AGE,GRADE) SELECT ID,NAME,AGE,GRADE FROM STUDENT_NEW;
Query OK, 2 rows affected (2.15 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM STUDENT;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  1 | LUNA |  20 |    80 |
|  2 | LUNA |  20 |    80 |
|  3 | NANA |  21 |    85 |
|  4 | TOM  |  19 |    88 |
|  5 | BOBO |  22 |    88 |
|  6 | BOBY |  22 |    98 |
+----+------+-----+-------+
6 rows in set (0.00 sec)

更新数据

mysql> UPDATE STUDENT SET GRADE =90 WHERE ID=1;
Query OK, 1 row affected (0.07 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> SELECT * FROM STUDENT;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  1 | LUNA |  20 |    90 |
|  2 | LUNA |  20 |    80 |
|  3 | NANA |  21 |    85 |
|  4 | TOM  |  19 |    88 |
|  5 | BOBO |  22 |    88 |
|  6 | BOBY |  22 |    98 |
+----+------+-----+-------+
6 rows in set (0.00 sec)

删除数据

mysql> DELETE FROM STUDENT WHERE ID=6;
Query OK, 1 row affected (0.05 sec)

mysql> SELECT * FROM STUDENT;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  1 | LUNA |  20 |    90 |
|  2 | LUNA |  20 |    80 |
|  3 | NANA |  21 |    85 |
|  4 | TOM  |  19 |    88 |
|  5 | BOBO |  22 |    88 |
+----+------+-----+-------+
5 rows in set (0.00 sec)

mysql> DELETE FROM STUDENT WHERE GRADE BETWEEN 80 AND 85;
Query OK, 2 rows affected (0.05 sec)

mysql> SELECT * FROM STUDENT;
+----+------+-----+-------+
| ID | NAME | AGE | GRADE |
+----+------+-----+-------+
|  1 | LUNA |  20 |    90 |
|  4 | TOM  |  19 |    88 |
|  5 | BOBO |  22 |    88 |
+----+------+-----+-------+
3 rows in set (0.00 sec)

删除所有数据

mysql> DELETE FROM STUDENT;
Query OK, 3 rows affected (0.06 sec)

mysql> SELECT * FROM STUDENT;
Empty set (0.00 sec)