Re: Why this SQL does not work?

The way I understand it is rownum does not exist until the data set is returned. The first row returned therefore is rownum = 1 because it is the first row in the dataset, but you are looking for rownum = 5, so it throws that one away. The next row is returned and again is rownum = 1 because it is now the first row in the dataset, but again you are looking for rownum = 5, so it throws that away too. And so on and so on. Basically, it never gets to rownum = 5. So you can use rownum = 1 or rownum < anything more than 1, but nothing else.

At 01:44 PM 7/11/01 -0800, you wrote:
>List,
>
>Following are two SQL statements. The first SQL statement works OK (where
>ROWNUM < 5 is used). The second SQL statement does not return any rows
>(where ROWNUM = 5 is used). This table contains 200 records.
>
>First SQL statement
>-------------------
>SELECT * FROM
> (SELECT PROCESSED_DATE
> FROM TRADES WHERE PROCESSED_STATUS = 0
> ORDER BY ENTRY_DATE)
> WHERE ROWNUM < 5
>
>Second SQL statement
>--------------------
>SELECT * FROM
> (SELECT PROCESSED_DATE
> FROM TRADES WHERE PROCESSED_STATUS = 0
> ORDER BY ENTRY_DATE)
> WHERE ROWNUM = 5
>
>---------------
>Question:
>
>Why second SQL statement does not work?
>
>I would be thankful for the clarification.
>
>Thanks,
>
>Rao
>Maheswara.Rao_at_Sungardp3.com
>
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