通过子查询选择top n是行不通的 [英] selecting top n via a subquery isn't working

问题描述

我正在使用的SQL语句是 -

展开 | 选择 | Wrap | 行号

解决方案

嗨


我想我可能会尝试一下这个

展开 | 选择 | 换行 | 行号

< blockquote>感谢您的回复。


您建议的陈述给出了奇怪的输出！对于一个bird_id，它已经复制了每个记录6次 - 现在只有一个bird_id。


即。


bird_id，date


1 01/01/2001

1 01/01/2001

1 01/01/2001

1 01/01/2001

1 01/01/2001

1 01/01/2001

1 01/01/2001

1 02/01/2001

1 02/01/2001

1 02/01/2001

1 02/01/2001

1 02/01/2001

1 02/01/2001

1 02/01/2001


我尝试在子查询中使用GROUP BY函数也无济于事。我真的坚持这个并将继续搜索谷歌。


Lizy

在没有任何数据知识的情况下很难知道你是什么期待。


我假设其他三个领域也都被重新调整!!


MTB

The SQL statement I am using is -

Expand|Select|Wrap|Line Numbers

解决方案

Hi

I think I might try it likr this

Expand|Select|Wrap|Line Numbers

Thank you for replying.

The statement you suggested has given a bizarre output! For a single bird_id it has duplicated each record 6 times - there is now only one bird_id.

ie.

bird_id, date

1 01/01/2001
1 01/01/2001
1 01/01/2001
1 01/01/2001
1 01/01/2001
1 01/01/2001
1 01/01/2001
1 02/01/2001
1 02/01/2001
1 02/01/2001
1 02/01/2001
1 02/01/2001
1 02/01/2001
1 02/01/2001

I tried using a GROUP BY function within the subquery to no avail either. I am really stuck on this and will continue to search google.

Lizy

Without any knowledge of you data it is hard to know what you are expecting.

I assume the other three fields are also retuned also!!

MTB

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