# Mysql常见语法

status: Idea tags: 数据库 Created time: August 27, 2023 9:59 PM

MySQL是一个常用的关系型数据库管理系统，下面列举一些MySQL常用的语法：

1. 创建数据库：

   ```sql
   CREATE DATABASE database_name;
   ```
2. 选择数据库：

   ```sql
   USE database_name;
   ```
3. 创建表：

   ```sql
   CREATE TABLE table_name (
     column1 datatype constraints,
     column2 datatype constraints,
     ...
   );
   ```
4. 插入数据：

   ```sql
   INSERT INTO table_name (column1, column2, ...)
   VALUES (value1, value2, ...);
   ```
5. 查询数据：

   ```sql
   SELECT column1, column2, ...
   FROM table_name
   WHERE conditions;
   ```
6. 更新数据：

   ```sql
   UPDATE table_name
   SET column1 = value1, column2 = value2, ...
   WHERE conditions;
   ```
7. 删除数据：

   ```sql
   DELETE FROM table_name
   WHERE conditions;
   ```
8. 添加列：

   ```sql
   ALTER TABLE table_name
   ADD column_name datatype constraints;
   ```
9. 修改列：

   ```sql
   ALTER TABLE table_name
   MODIFY column_name datatype constraints;
   ```
10. 删除列：

    ```sql
    ALTER TABLE table_name
    DROP COLUMN column_name;
    ```
11. 创建索引：

    ```sql
    CREATE INDEX index_name
    ON table_name (column1, column2, ...);
    ```
12. 删除索引：

    ```sql
    DROP INDEX index_name
    ON table_name;
    ```


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