SQL CE DISTINCT集合 [英] SQL CE DISTINCT AGGREGATE

问题描述

SQL CE是否具有使用聚合函数中不同的功能？
我需要类似

Does SQL CE has the ability to use distinct in aggregate functions? I need something like

SELECT count(distinct date) FROM table

这是简化的查询，我已经在原始查询中使用了GROUP BY。

This is simplified query and I already have GROUP BY used in original one.

推荐答案

SQL Server CE（当前版本）不支持count（distinct）

SQL Server CE (current version) does not support count(distinct)

解决方法是GROUP BY，听起来像您正在使用

The workaround is a GROUP BY, which sounds like what you are using

select count(*) from (
    select distinct date from tbl
) x

或者是否涉及其他字段

select groupcol, count(*)
from (
    select groupcol, date
    from tbl
    group by groupcol, date
) x
group by groupcol

这篇关于SQL CE DISTINCT集合的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！