我写了一个内部连接来从一个数据库中的三个表中提取信息。当我运行查询时,我得到两行返回,第二行是第一行的副本。我希望只有一行被返回?为什么SQL查询在只有一行存在时返回两行?
查询:
mysql> SELECT euroapps.id, euroapps.name, euroapps.imageurl, euroapps.website,
euroapps.developer, euroapps.description, euroapps.created, euroapps.iphone,
euroapps.ipodtouch, euroapps.ipad, app_detail.screen1 , app_detail.screen2,
app_detail.screen3, app_detail.screen4, application_price.retail_price
FROM euroapps INNER JOIN app_detail ON euroapps.id = app_detail.id
INNER JOIN application_price ON euroapps.id= application_price.application_id
WHERE euroapps.id = 353783927;
返回两行,而这一个只返回一个行(和预期)
mysql> SELECT euroapps.id, euroapps.name, euroapps.imageurl, euroapps.website,
euroapps.developer, euroapps.description, euroapps.created, euroapps.iphone,
euroapps.ipodtouch, euroapps.ipad, app_detail.screen1 , app_detail.screen2,
app_detail.screen3, app_detail.screen4
FROM euroapps INNER JOIN app_detail ON euroapps.id = app_detail.id
WHERE euroapps.id = 353783927;
此查询是否返回2行'select * from application_price WHERE application_price.application_id = 353783927;'?如果是这样,那就是答案。 – Augusto 2011-04-28 16:07:28