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what is the difference between rownum,rowid

Total Answers and Comments: 6

Last Update: June 30, 2009 Asked by: senthil

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Best Rated Answer

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Submitted by: rishipahuja

rowid has a physical significance i.e you can read a row if you know rowid. It is complete physical address of a row.

While rownum is temporary serial number allocated to each returned row during query execution.

Above answer was rated as good by the following members:
shinymoon29

July 27, 2006 02:20:50

Anurag puranik

RE: what is the difference between rownum,rowid

Rownum is just the serial No of your output while Rowid is automatically generated unique id of a row an it is generated at the time of insertion of row.

Rownum is numeric and rowid is 16 bit hexadecimal no.

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August 06, 2006 03:55:29

rishipahuja

Member Since: August 2006 Contribution: 2

RE: what is the difference between rownum,rowid

rowid has a physical significance i.e you can read a row if you know rowid. It is complete physical address of a row.

While rownum is temporary serial number allocated to each returned row during query execution.

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2 0

Overall Rating: +2

August 29, 2006 04:40:53

vidhya

RE: what is the difference between rownum,rowid

very good answer

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September 12, 2008 02:23:24

lanka_satya

Member Since: January 2008 Contribution: 16

RE: what is the difference between rownum,rowid

rownum is generated for the data retrieved and stored in an implicit cursor so depending on the outcum it may varry where as rowid is generated automatically for creation of every row hence forth if we want retrive a particular row in a table we can abosolutelt do that if we can give rowid.....

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November 24, 2008 08:04:41

nalinbit

Member Since: November 2008 Contribution: 3

RE: what is the difference between rownum,rowid

rownum is a pseudo column which is generated for query data set at runtime. while rowid is the physical address of the row and hence definition suggest rowid for a row will never change but row num will always change.

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June 30, 2009 08:42:17

venugopalreddy.net

Member Since: June 2009 Contribution: 1

RE: what is the difference between rownum,rowid

rownum is the temp num assigned for the return rows per statement query
It will change as per the query statement.
It can be used with 1 or < 10 id number .
Where as rowid is the id assigned by the
Oracle while creating record in database. It is permanent & we can query with sign & it will not change
or depend on query.

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