Mac修改Mysql8.0密码

文章目录

• DML
• 1. 基本介绍
• 2. 添加数据
• 3. 修改数据
• 4. 删除数据

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专栏链接：数据库MySQL

DML

1. 基本介绍

DML英文全称是Data Mainipulation Language（数据操作语言），用来对数据库中表的数据记录进行增删改操作。

三大关键字：

2. 添加数据

1. 给指定字段添加数据

INSERT INTO 表名(字段名1, 字段名2, ...) VALUES (值1, 值2, ...);

案例：

示例代码：

mysql> 
mysql> insert into emloyee (id, workno, name, gender, age, idcard, entrydate) values (1, '1', '张三', '男', 15, '012345678912345678', '2001-01-01');
Query OK, 1 row affected (0.00 sec)

mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  1 | 1      | 张三 | 男     |  15 | 012345678912345678 | 2001-01-01 |
+----+--------+------+--------+-----+--------------------+------------+
1 row in set (0.03 sec)

mysql> 

2. 给全部字段添加数据

INSERT INTO 表名 VALUES (值1, 值2, ...);

案例：

示例代码：

mysql> 
mysql> insert into emloyee values(2, '2', '李四', '男', 18, '012345678912345679', '2002-02-02');
Query OK, 1 row affected (0.01 sec)

mysql> 
mysql> 
mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  1 | 1      | 张三 | 男     |  15 | 012345678912345678 | 2001-01-01 |
|  2 | 2      | 李四 | 男     |  18 | 012345678912345679 | 2002-02-02 |
+----+--------+------+--------+-----+--------------------+------------+
2 rows in set (0.04 sec)

mysql> 

3. 批量添加数据

INSERT INTO 表名 (字段名1, 字段名2, ...) VALUES (值1, 值2, ...),(值1, 值2, ...);

INSERT INTO 表名 VALUES(值1, 值2, ...), (值1, 值2, ...), (值1, 值2, ...);

案例：

示例代码：

mysql> 
mysql> insert into emloyee (id, workno, name, gender, age, idcard, entrydate) values (3,'3', '王五', '男', 13, '012345678901234567', '2003-03-03'),(4, '4', '哈哈', '男', 14, '012345678912345689', '2004-04-04');
Query OK, 2 rows affected (0.01 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  1 | 1      | 张三 | 男     |  15 | 012345678912345678 | 2001-01-01 |
|  2 | 2      | 李四 | 男     |  18 | 012345678912345679 | 2002-02-02 |
|  3 | 3      | 王五 | 男     |  13 | 012345678901234567 | 2003-03-03 |
|  4 | 4      | 哈哈 | 男     |  14 | 012345678912345689 | 2004-04-04 |
+----+--------+------+--------+-----+--------------------+------------+
4 rows in set (0.04 sec)

mysql> 

注意：

3. 修改数据

基本语法：

UPDATE 表名 SET 字段名1=值1, 字段名2=值2, ...[WHERE条件];

注意：

案例1：

示例代码：

mysql> 
mysql> update emloyee set name='嘿嘿' where id=1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> 
mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  1 | 1      | 嘿嘿 | 男     |  15 | 012345678912345678 | 2001-01-01 |
|  2 | 2      | 李四 | 男     |  18 | 012345678912345679 | 2002-02-02 |
|  3 | 3      | 王五 | 男     |  13 | 012345678901234567 | 2003-03-03 |
|  4 | 4      | 哈哈 | 男     |  14 | 012345678912345689 | 2004-04-04 |
+----+--------+------+--------+-----+--------------------+------------+
4 rows in set (0.04 sec)

mysql> 

案例2：

示例代码：

ysql> 
mysql> update emloyee set name = '小马', gender = '女' where id=1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> 
mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  1 | 1      | 小马 | 女     |  15 | 012345678912345678 | 2001-01-01 |
|  2 | 2      | 李四 | 男     |  18 | 012345678912345679 | 2002-02-02 |
|  3 | 3      | 王五 | 男     |  13 | 012345678901234567 | 2003-03-03 |
|  4 | 4      | 哈哈 | 男     |  14 | 012345678912345689 | 2004-04-04 |
+----+--------+------+--------+-----+--------------------+------------+
4 rows in set (0.05 sec)

mysql> 

案例3：

示例代码：

mysql> 
mysql> update emloyee set entrydate='2020-05-20';
Query OK, 4 rows affected (0.01 sec)
Rows matched: 4  Changed: 4  Warnings: 0

mysql> 
mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  1 | 1      | 小马 | 女     |  15 | 012345678912345678 | 2020-05-20 |
|  2 | 2      | 李四 | 男     |  18 | 012345678912345679 | 2020-05-20 |
|  3 | 3      | 王五 | 男     |  13 | 012345678901234567 | 2020-05-20 |
|  4 | 4      | 哈哈 | 男     |  14 | 012345678912345689 | 2020-05-20 |
+----+--------+------+--------+-----+--------------------+------------+
4 rows in set (0.04 sec)

mysql> 

4. 删除数据

基本语法：

DELETE FROM 表名[WHERE 条件];

注意：

案例1：

示例代码：

mysql> 
mysql> delete from emloyee where gender='女';
Query OK, 1 row affected (0.00 sec)

mysql> 
mysql> 
mysql> select * from emloyee;
+----+--------+------+--------+-----+--------------------+------------+
| id | workno | name | gender | age | idcard             | entrydate  |
+----+--------+------+--------+-----+--------------------+------------+
|  2 | 2      | 李四 | 男     |  18 | 012345678912345679 | 2020-05-20 |
|  3 | 3      | 王五 | 男     |  13 | 012345678901234567 | 2020-05-20 |
|  4 | 4      | 哈哈 | 男     |  14 | 012345678912345689 | 2020-05-20 |
+----+--------+------+--------+-----+--------------------+------------+
3 rows in set (0.04 sec)

mysql> 

案例2：

示例代码：

mysql> delete from emloyee;
Query OK, 3 rows affected (0.01 sec)

mysql> 
mysql> 
mysql> 
mysql> select * from emloyee;
Empty set

mysql>