Big Performance Problems With Oracle DataReader in .Net

Question

I have a few Oracle procedures that generate/return a large amount of data that I need to write out to a file. I\'m currently trying to accomplish with a data-reader. It seems

Answer 1

What is the database actually doing ?

A query with a GROUP BY or and ORDER BY may need to generate the full result set, then sort/aggregate it before returning a row. A query scanning a large table may find 50 rows in the first couple of blocks, then read another hundred thousand blocks before it finds another one.

I suggest you ignore the VB code and post the database code.