SQL内部连接问题
以下SQL查询不工作。我认为错误在第一行SQL内部连接问题,sql,inner-join,Sql,Inner Join,以下SQL查询不工作。我认为错误在第一行 SELECT SUBSTRING(tbl_news.comment, 1, 250) as tbl_news.comment, tbl_news.id, tbl_news.date, tbl_news.subject, tbl_users.username FROM tbl_news INNER JOIN tbl_users ON tbl_news.creator = tbl_users.id ORDER B
SELECT
SUBSTRING(tbl_news.comment, 1, 250) as tbl_news.comment,
tbl_news.id, tbl_news.date, tbl_news.subject, tbl_users.username
FROM
tbl_news
INNER JOIN
tbl_users ON tbl_news.creator = tbl_users.id
ORDER BY
date DESC
我认为你的别名tbl_news.comment不允许有点。你犯了什么错误?它是什么味道的SQL?谢谢。试试这个:
SELECT SUBSTRING(tbl_news.comment, 1, 250) as comment,
tbl_news.id, tbl_news.date, tbl_news.subject, tbl_users.username FROM tbl_news
INNER JOIN tbl_users ON tbl_news.creator = tbl_users.id
ORDER BY date DESC
SELECT SUBSTRING(tbl_news.comment, 1, 250) as comment,
tbl_news.id, tbl_news.date, tbl_news.subject, tbl_users.username
FROM tbl_news
INNER JOIN tbl_users ON tbl_news.creator = tbl_users.id
ORDER BY date DESC
使用:
在SQL Server上,在列别名上使用单引号也适用于我:
SELECT SUBSTRING(tn.comment, 1, 250) AS 'tbl_news.comment',
tn.id,
tn.date,
tn.subject,
tu.username
FROM tbl_news tn
JOIN tbl_users tu ON tu.id = tn.creator
ORDER BY tn.date DESC
它不起作用了。错误是什么?什么不起作用?它应该做什么呢?它不工作也没用。我们需要知道错误和/或您期望得到的结果。对于DB查询,这就更难了,因为我们可能还需要了解模式。抱歉,不允许使用tbl_news.comment。这是SQL Server吗?如果是:什么版本?如果不是:它是什么数据库系统??两者的混合Lester-关于别名,你可能是对的,但问题应该是注释。+1有趣-不知道你可以为列创建虚线别名。。。你每天都在学习-@marc_s:最近在MySQL中使用了backticks,但我当然不推荐这种做法。我会为任何这样做的同事买以下东西:
SELECT SUBSTRING(tn.comment, 1, 250) AS 'tbl_news.comment',
tn.id,
tn.date,
tn.subject,
tu.username
FROM tbl_news tn
JOIN tbl_users tu ON tu.id = tn.creator
ORDER BY tn.date DESC