Question

我正在尝试做一个显示所有评论的博客，用户将能够在以前发布的评论中发表回复评论，然后在sql查询中进行排序，这样他们就会出现以便我不断收到错误。< / p>

SELECT c.userid, c.comment, c.reply, u.username, c.createdat, c.image, c.username as
ComUser FROM Bundle:Comments c LEFT JOIN Bundle:Users u WITH c.userid = u.id
WHERE c.articleid = 1 ORDER BY (CASE WHEN (c.parentid = 0) THEN c.id ELSE c.parentid END) 
c.createdat ASC

给出错误：[语法错误]第0行，第515行：错误：字符串的预期结束，得到'CASE'

甚至尝试过正常的方式

ORDER BY IF(c.parentid = 0, c.id, c.parentid), c.createdat ASC

给出错误：[语法错误]第0行，第515行：错误：字符串的预期结束，得到'（'

当我在正常的sql代码（不是doctrine）中使用正常的ORDERY BY IF（）时，它可以正常工作。

Answer 1

看起来你只是有一个错字。您的整体语法是正确的。

ORDER BY CASE WHEN (c.parentid = 0) THEN c.id ELSE .parentid END c.createdat ASC

应该是

ORDER BY CASE WHEN (c.parentid = 0) THEN c.id ELSE c.parentid END, c.createdat ASC

Answer 2

AWSOME !!! 谢谢你的帮助，我刚刚得到它！

我的解决方案：

SELECT c.userid, c.comment, c.reply, u.username, c.createdat, c.image, c.username as
ComUser, (CASE WHEN (c.parentid = 0) THEN c.id ELSE c.parentid END) as OrderByComm
FROM Bundle:Comments c LEFT JOIN Bundle:Users u WITH c.userid = u.id
WHERE c.articleid = 1 ORDER BY OrderByComm, c.createdat ASC

我在选择部分通过计算完成了订单。

IF语句按照Doctrine 2查询Symfony 2的条款顺序排列

2 个答案: