- 查询语句:
sql
SELECT * FROM table_name; //查询表中所有列
SELECT column_name FROM table_name; //查询指定列
SELECT * FROM table_name WHERE condition; //条件查询
SELECT column_name FROM table_name WHERE condition ORDER BY column_name; //排序查询
SELECT COUNT(*) FROM table_name; //统计查询
SELECT * FROM table_name LIMIT n; //限制查询结果的前n行
- 插入语句:
sql
INSERT INTO table_name (column_name1, column_name2, ...) VALUES (value1, value2, ...);
- 更新语句:
sql
UPDATE table_name SET column_name1=value1, column_name2=value2 WHERE condition;
- 删除语句:
sql
DELETE FROM table_name WHERE condition;
- 创建表:
sql
CREATE TABLE table_name
(
column_name1 type,
column_name2 type,
...
);
- 修改表:
sql
ALTER TABLE table_name
ADD column_name type; //增加列
DROP COLUMN column_name; //删除列
MODIFY COLUMN column_name type; //修改列类型
- 删除表:
sql
DROP TABLE table_name;
- 其他语句:
sql
SHOW DATABASES; //显示数据库列表
USE database_name; //选择数据库
SHOW TABLES; //显示数据表列表
DESC table_name; //显示数据表结构
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