asked on

TOAD implementation

Hey experts!

I have a general question - IF your Oracle (9.2 or 10g) database has say, a terabyte of data in a single table, and you say select * from that table; TOAD somehow manages to return the first rows of the query, and let you page through the rest...

If you drag the scroll bar to the bottom, you will wait a long time.. then finally see the last screen full of records...

The question is: how is this accomplished? It seems that all the results are not returned to the client, but instead are kept on the server... I'm thinking as a snapshot(?). If this is true, how do you page through a snapshot result set? any ideas?

alternately, what is the best way to not kill your app with out of memory errors on absurdely large result sets?

thanks for comments.

SOLUTION

sujit_kumar

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

ASKER CERTIFIED SOLUTION

JohnRBailey

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

randyd

ASKER

it turns out that TOAD does in fact store the entire result set in memory when you scroll to the bottom.

What got me on this tamgent was a message that stated Snapshot too old after i failed to scroll to the bottom for awhile... sorta makes sense that the internal mechanism is a snapshop - but its just a read consistent cursor to the client.

anyway, i was aware of first_rows hints etc. but will split points among all respondents.. thanks