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mysql add, delete, modify and query statements

mysql增删改查语句例子

1、增加记录在 MySQL 中,我们可以使用 INSERT INTO 语句添加一条新的记录。示例:INSERT INTO students(name, age, gender) values('Tom', 23, 'male');这个语句将会向 students 表中插入一条名为 Tom,年龄为 23,性别为男性的记录。

2、删除记录通常使用 DELETE FROM 语句,语法如下:DELETE FROM students WHERE id = 3;这条语句将会从 students 表中删除指定 id 的学生记录。

3、修改记录通常使用 UPDATE 语句,语法如下:UPDATE students SET age = 24 WHERE name = 'Tom';这条语句将会更改名为 Tom 的学生的年龄为 24。

4、查询记录通常使用 SELECT 语句,语法如下:SELECT * FROM students;这条语句将会查询 students 表中的所有记录。我们也可以根据条件查询指定的记录,例如:SELECT * FROM students WHERE age > 20;这条语句将会查询所有年龄大于 20 岁的学生记录。

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