ChatGPT输出MySQL常用语法汇总

Posted 2023-04-04 我是小bā吖

以下是MySQL常用的语法汇总：

1. 创建数据库
   CREATE DATABASE database_name;

2. 删除数据库
   DROP DATABASE database_name;

3. 创建表
   CREATE TABLE table_name (
   column1 datatype,
   column2 datatype,
   column3 datatype,
   …
   );

4. 删除表
   DROP TABLE table_name;

5. 插入数据
   INSERT INTO table_name (column1, column2, column3, …) VALUES (value1, value2, value3, …);

6. 更新数据
   UPDATE table_name SET column1 = value1, column2 = value2, … WHERE condition;

7. 删除数据
   DELETE FROM table_name WHERE condition;

8. 查询数据
   SELECT column1, column2, … FROM table_name WHERE condition;

9. 排序
   SELECT column1, column2, … FROM table_name ORDER BY column1 ASC/DESC;

10. 分组
    SELECT column1, SUM(column2) FROM table_name GROUP BY column1;

11. 连接
    SELECT column1, column2, … FROM table_name1 JOIN table_name2 ON condition;

12. 子查询
    SELECT column1 FROM table_name WHERE column2 = (SELECT column3 FROM table_name2 WHERE condition);

13. 聚合函数
    SELECT COUNT(column1), SUM(column2), AVG(column3), MAX(column4), MIN(column5) FROM table_name;

14. 数据类型
    INT, BIGINT, FLOAT, DOUBLE, CHAR, VARCHAR, TEXT, DATE, TIME, DATETIME, TIMESTAMP

15. 约束
    PRIMARY KEY, FOREIGN KEY, UNIQUE, NOT NULL, CHECK

16. 创建索引
    CREATE INDEX index_name ON table_name (column1, column2, …);

17. 删除索引
    DROP INDEX index_name ON table_name;

18. 外键约束
    ALTER TABLE table_name ADD FOREIGN KEY (column1) REFERENCES table_name2(column2);

19. 修改表
    ALTER TABLE table_name ADD column_name datatype;

20. 删除列
    ALTER TABLE table_name DROP column_name;

21. 修改列
    ALTER TABLE table_name MODIFY column_name datatype;

22. 添加约束
    ALTER TABLE table_name ADD CONSTRAINT constraint_name UNIQUE (column1, column2, …);

23. 删除约束
    ALTER TABLE table_name DROP CONSTRAINT constraint_name;

24. 视图
    CREATE VIEW view_name AS SELECT column1, column2, … FROM table_name WHERE condition;

25. 存储过程
    CREATE PROCEDURE procedure_name (IN param1 datatype1, OUT param2 datatype2) BEGIN SELECT column1, column2, … FROM table_name WHERE condition; END;

26. 触发器
    CREATE TRIGGER trigger_name BEFORE/AFTER INSERT/UPDATE/DELETE ON table_name FOR EACH ROW BEGIN … END;

27. 用户管理
    CREATE USER user_name@localhost IDENTIFIED BY ‘password’;

28. 授权
    GRANT SELECT, INSERT, UPDATE, DELETE ON database_name.table_name TO user_name@localhost;

29. 撤销授权
    REVOKE SELECT, INSERT, UPDATE, DELETE ON database_name.table_name FROM user_name@localhost;

30. 导入数据
    LOAD DATA INFILE ‘file_name’ INTO TABLE table_name;

31. 导出数据
    SELECT column1, column2, … INTO OUTFILE ‘file_name’ FROM table_name;

Mysql 简单查询语句汇总

把一些mysql的常用语法进行下汇总

1.简单语句

/*websites  表名   NAME alexa url country  字段*/
SELECT * FROM websites;                      /* 查询表所有数据 */

SELECT NAME FROM websites;                   /* 查询表字段数据 */

SELECT * FROM websites where name = "广西";   /* 查询表字段下条件数据 */

SELECT * from websites where name like "_o%"; /* 模糊查询表下数据 */

SELECT * FROM websites where id BETWEEN "1" AND "5";    /* 查询表下字段范围数据 */

SELECT * FROM websites WHERE name in ("广西","百度");    /* 查询表字段下固定条件数据 */

SELECT DISTINCT country FROM Websites;                  /* 查询去重值 */

SELECT * FROM Websites WHERE country = "CN" AND alexa > 50;  /*查询表下范围条件数据*/

SELECT * FROM Websites WHERE country = "USA" OR country="sh"; /* 查询表下条件不同值 */

SELECT * FROM Websites ORDER BY alexa;                      /* 查询表下值排序结果 */

SELECT * FROM Websites ORDER BY alexa DESC;                 /* 查询表下排序结果降序 */

SELECT * FROM Websites LIMIT 2;      /* 查询表下范围数据 */

SELECT name as zzz from websites;    /*别名查询表下数据*/

2.分页

select _column,_column from _table [where Clause] [limit N][offset M]

select * : 返回所有记录
limit N : 返回 N 条记录
offset M : 跳过 M 条记录, 默认 M=0, 单独使用似乎不起作用
limit N,M : 相当于 limit M offset N , 从第 N 条记录开始, 返回 M 条记录
实现分页：

select * from _table limit (page_number-1)*lines_perpage, lines_perpage

或

select * from _table limit lines_perpage offset (page_number-1)*lines_perpage