SQL select into 语句
SELECT INTO 语句的作用是从一个表复制数据,然后把数据插入到另一个新表中。
select into 语句语法:
SELECT *
INTO newtable [IN externaldb]
FROM table1;
或者只复制希望的列插入到新表中:
SELECT column_name(s)
INTO newtable [IN externaldb]
FROM table1;
注意:MySQL 数据库不支持 SELECT ... INTO 语句,但支持 INSERT INTO ... SELECT 。
select into 语句实例
创建 Websites 的备份复件:
SELECT *
INTO WebsitesBackup2016
FROM Websites;
只复制一些列插入到新表中:
SELECT name, url
INTO WebsitesBackup2016
FROM Websites;
只复制中国的网站插入到新表中:
SELECT *
INTO WebsitesBackup2016
FROM Websites
WHERE country='CN';
复制多个表中的数据插入到新表中:
SELECT Websites.name, access_log.count, access_log.date
INTO WebsitesBackup2016
FROM Websites
LEFT JOIN access_log
ON Websites.id=access_log.site_id;
提示:SELECT INTO 语句可用于通过另一种模式创建一个新的空表。只需要添加促使查询没有数据返回的 WHERE 子句即可:
SELECT *
INTO newtable
FROM table1
WHERE 1=0;