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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Why this SQL does not work?
>From the Oracle docs (SQL Reference)
"For each row returned by a query, the ROWNUM pseudocolumn returns a number
indicating the order in which Oracle selects the row from a table or set of
joined rows. The first row selected has a ROWNUM of 1, the second has 2, and
so on.
...
Conditions testing for ROWNUM values greater than a positive integer are
always false. For example, this query returns no rows:
SELECT * FROM emp
WHERE ROWNUM > 1; The first row fetched is assigned a ROWNUM of 1 and makes the condition false. The second row to be fetched is now the first row and is also assigned a ROWNUM of 1 and makes the condition false. All rows subsequently fail to satisfy the condition, so no rows are returned."
Henry
-----Original Message-----
Sent: Wednesday, July 11, 2001 6:00 PM
To: Multiple recipients of list ORACLE-L
First guess .... There are only 4 rows of data returned ??
Change the first query to
Where rownum <= 5
and let us know if you actually get that 5th row. If you did not then I would say that the queries are both working but there are only 4 rows that match the criteria.
-----Original Message-----
Sent: Wednesday, July 11, 2001 4:44 PM
To: Multiple recipients of list ORACLE-L
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
FROM TRADES WHERE PROCESSED_STATUS = 0
ORDER BY ENTRY_DATE)
WHERE ROWNUM < 5
Second SQL statement
FROM TRADES WHERE PROCESSED_STATUS = 0
ORDER BY ENTRY_DATE)
Why second SQL statement does not work?
I would be thankful for the clarification.
Thanks,
Rao
Maheswara.Rao_at_Sungardp3.com
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Rao, Maheswara INET: Maheswara.Rao_at_Sungardp3.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Kevin Lange INET: kgel_at_ppoone.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Henry Poras INET: Henry.Poras_at_ctp.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Wed Jul 11 2001 - 16:18:33 CDT
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