Strange thing noticed with a view and group by

Question

Hi all, Could anybody please tell me what could be the problem if you have come across it ever.
I am using a view which is fetching 4 million rows from another db thru a dblink. In the view query this data is joined with two other small temporary tables and the output is taken out.
The whole process is like this...
1.Create the two temporary tables..
2. Alter the view to compile;( as these temporary tables are dropped after the whole process)
3. insert into the target table using another query by taking the data from the VIEW
4. drop the temporary tables.
All these are in a single script.
In the insert statement I use a group by in the select statement to produce sum of three columns.
the ideal output is as giiven below:
total rows= 4.7 million.
after the group by i should get 293,356 rows( i tested it after taking all the rows from the view into my db and did a group by on it with the required columns)
Now the group by is done directly by taking the data from the view and inserting into the final table.
When i ran the script for the first time I got this 293,356 rows... The second time I ran it gave me only 73090 rows. But the sum total of those 3 columns are exctly same as that of 293,356 rows. I donot change the number of columns in group by or anything like that... what i am doing is just running it again....
Can anybody tell me why it gives different number of rows at different times when the same script is run without any changes...( There is no difference in the original number of rows too..)
Thanks
Edited by: user626688 on Oct 17, 2008 12:26 PM

Answer 1

Way not enough information.
Assume you have Oracle to Oracle connection here (with your DB link). What version are BOTH databases on. No idea what the view looks like, or how you use it, or what these 'temporary tables' you create on the fly do.
Can you put together a small example of this which recreates your problem? We don't have your tables, your script, your ability to run queries and check things, so there's really not much anyone can do to help you with this.
The simplest explanation is usually the correct one, so although it's possible you've hit an internal Oracle bug, i'd put my money in there being a flaw in your processing, it's where the safe money is. Though there could be a bug with view merging, or the DB link, or .....