Sql server 使用innerjoin MSSQL 2005和VBscript从列中选择不同的用户

使用Microsoft SQL 2005和VBscript

我正在为一个网站制作一个信息部分。我有一个名为mail的表。列包括messageid、sender、receiver、body和created。Messageid、sender和receiver都是BIGINT数据类型。body列是nvarchar（max）数据类型。创建的是日期时间数据类型

对于本例，假设用户John的userid为100

我试图隔离发送John消息或接收John消息的不同用户，并按创建列的时间（或按messageid）对用户进行排序。我尝试的查询要么失败，要么多次向同一用户查询

此查询：

SQL = "SELECT DISTINCT otherperson FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson, messageid from message where message.receiver= '100' ORDER BY messageid DESC "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson, messageid from message where message.sender= '100' ORDER BY messageid DESC ) results "
SQL = SQL & "ORDER BY messageid"

给出错误：ORDER BY子句在视图、内联函数、派生表、子查询和公共表表达式中无效，除非还指定了TOP或FOR XML

SQL = "SELECT DISTINCT otherperson, messageid FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson, messageid from message where message.receiver= '100' ORDER BY messageid DESC "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson, messageid from message where message.sender= '100' ORDER BY messageid DESC ) results "
SQL = SQL & "ORDER BY messageid"

SQL = "SELECT otherperson FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson from message where message.receiver= '100' "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson from message where message.sender= '100' ) results "

还提供了一个错误：ORDER BY子句在视图、内联函数、派生表、子查询和公共表表达式中无效，除非还指定了TOP或FOR XML

SQL = "SELECT DISTINCT otherperson, messageid FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson, messageid from message where message.receiver= '100' ORDER BY messageid DESC "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson, messageid from message where message.sender= '100' ORDER BY messageid DESC ) results "
SQL = SQL & "ORDER BY messageid"

SQL = "SELECT otherperson FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson from message where message.receiver= '100' "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson from message where message.sender= '100' ) results "

此查询确实有效，并为我提供从John接收消息和向John发送消息的不同用户，但我无法按每个不同用户的消息时间排序

您可以使用messageid（这是一个唯一的数字，递增1）或created（这是一个具有日期时间数据类型的列）

有人能帮忙吗

---

TIA有两个多余的括号。
以下是您的查询现在的外观：

SELECT DISTINCT otherperson 
FROM 
(
    SELECT DISTINCT sender AS otherperson from message where (message.receiver= '100'
    UNION
    SELECT DISTINCT receiver AS otherperson from message where (message.sender= '100'
) results
ORDER BY messageid

只需删除

（

在

message.receiver

和

message.sender

之前）

[编辑]删除最顶端的

DISTINCT

。它是多余的。

UNION

不会返回重复的值，无需执行额外的DISTINCT

---

如果您确实需要

DISTINCT

，您可以将

orderbymessageid

替换为

orderby1

-按第一列排序。

我认为您需要解决的第一件事是没有

messageid

字段可供排序。您只有一个字段来自通过两个SELEC创建的表T声明

此外，还有两个不需要的括号。两个括号都是这样的：

WHERE (message.

SQL = "SELECT DISTINCT otherperson, messageid FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson, messageid from message where message.receiver= '100'  "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson, messageid from message where message.sender= '100' ) results "
SQL = SQL & "ORDER BY messageid"

这些都是你的疑问

最后，也是这里真正的问题，您的子查询中有ORDER BY语句（

ORDER BY messageid DESC

），但您不能这样做。删除这些语句，您将修复此编译器错误

删除这两条order by语句，更改order by或添加该列，并修复括号，您就可以开始了

您的最终声明应如下所示：

WHERE (message.

SQL = "SELECT DISTINCT otherperson, messageid FROM ("
SQL = SQL & "SELECT DISTINCT sender AS otherperson, messageid from message where message.receiver= '100'  "
SQL = SQL & "UNION "
SQL = SQL & "SELECT DISTINCT receiver AS otherperson, messageid from message where message.sender= '100' ) results "
SQL = SQL & "ORDER BY messageid"

---

对不起，我已经删除了它们，我在发布时忘记了更新message@Patriotec-我更新了我的答案。根本问题是子查询中的ORDER BY语句。删除这两个语句并修复最终的ORDER BY，以便有一个字段进行排序，您将解决问题。对不起，我已经删除了它们，我在发布时忘了更新我听到了这个消息