常用sql语句整理:mysql

TIGERB

  • 增加一张表
CREATE TABLE `table_name`(
  ...
  )ENGINE=InnoDB DEFAULT CHARSET=utf8;
  • 增加记录
INSERT INTO `your_table_name`(`column_name`)
VALUES
('your_value_one'),
('your_value_two');
  • 增加字段
ALTER TABLE `your_table_name`
ADD `your_column_name` ...
AFTER `column_name`;
  • 增加索引

    • 主键
    ALTER TABLE `your_table_name`
    ADD PRIMARY KEY your_index_name(your_column_name);
    • 唯一索引
    ALTER TABLE `your_table_name`
    ADD UNIQUE your_index_name(your_column_name);
    • 普通索引
    ALTER TABLE `your_table_name`
    ADD INDEX your_index_name(your_column_name);
    • 全文索引
    ALTER TABLE `your_table_name`
    ADD FULLTEXT your_index_name(your_column_name);

  • 逐行删除
DELETE FORM `table_name`
WHERE ...;
  • 清空整张表
TRUNCATE TABLE `your_table_name`;
  • 删除表
DROP TABLE `your_table_name`;
  • 删除字段
ALTER TABLE `your_table_name`
DROP `column_name`;
  • 删除索引
ALTER TABLE `your_table_name`
DROP INDEX your_index_name(your_column_name);

  • 变更数据
UPDATE `table_name`
SET column_name=your_value
WHERE ...;
  • 变更字段
ALTER TABLE `your_table_name`
CHANGE `your_column_name` `your_column_name` ...(变更);
  • 变更字段值为另一张表的某个值
UPDATE `your_table_name`
AS a
JOIN `your_another_table_name`
AS b
SET a.column = b.another_column
WHERE a.id = b.a_id...;

  • 普通查询
SELECT `column_name_one`, `column_name_two`
FROM `table_name`;
  • 关联查询
SELECT *
FROM `your_table_name`
AS a
JOIN `your_anther_table_name`
AS b
WHERE a.column_name = b.column_name...;
  • 合计函数条件查询:WHERE 关键字无法与合计函数一起使用
SELECT aggregate_function(column_name)
FROM your_table_name
GROUP BY column_name
HAVING aggregate_function(column_name)...;
  • 同一个实例下跨库查询
SELECT *
FROM database_name.your_table_name
AS a
JOIN anther_database_name.your_anther_table_name
AS b
WHERE a.column_name = b.column_name...;

复制一张表结构

CREATE `your_table_name`
LIKE `destination_table_name`;

完全复制一张表:表结构+全部数据

CREATE `your_table_name`
LIKE `destination_table_name`;

INSERT INTO `your_table_name`
SELECT *
FROM `destination_table_name`;

附录:mysql常用命令

  • 登陆: mysql -h host -u username -p
  • 列出数据库:SHOW DATABESES;
  • 列出表:SHOW TABLES;
  • 表结构:DESC table_name;
  • 使用一个数据库:USE database_name;
  • 导入:source 'file';
  • 导出:mysqldump -h 127.0.0.1 -u root -p "database_name" "table_name" --where="condition" > file_name.sql;

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