SQL 选择进入
通过 SQL,您可以从一个表复制信息到另一个表。
SELECT INTO 语句从一个表复制数据,然后把数据插入到另一个新表中。
SQL SELECT INTO 语句
SELECT INTO 语句从一个表复制数据,然后把数据插入到另一个新表中。
SQL SELECT INTO 语法
我们可以复制所有的列插入到新表中:
//SELECT *
//INTO newtable [IN externaldb]
//FROM table1;
//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;
INTO newtable [IN externaldb]
FROM table1;
提示:新表将会使用 SELECT 语句中定义的列名称和类型进行创建。您可以使用 AS 子句来应用新名称。 |
SQL SELECT INTO 实例
创建 Customers 的备份复件:
SELECT *
INTO WebsitesBackup2016
FROM Websites;
INTO WebsitesBackup2016
FROM Websites;
请使用 IN 子句来复制表到另一个数据库中:
SELECT *
INTO WebsitesBackup2016 IN 'Backup.mdb'
FROM Websites;
INTO WebsitesBackup2016 IN 'Backup.mdb'
FROM Websites;
只复制一些列插入到新表中:
SELECT name,
url
INTO WebsitesBackup2016
FROM Websites;
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';
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;
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;
INTO newtable
FROM table1
WHERE 1=0;