As detailed here and confirmed here, the default number of rows Oracle returns at time when querying for data over JDBC is 10. I am working on an app that to has to read and compare lots of data from our database. I thought that if we just increase defaultRowPrefetch to be something like 1000, then surely our app would perform faster. As it turned out, it performed slower and by about 20%.

We then decided to just slowly increase the number from 10 and see how it performs. We've seen about a 10% increase by setting it somewhere between 100 and 200. I would have never guessed, however, that setting it higher would make our app perform more slowly. Any ideas why this might happen?

Thanks!

EDIT:

Just for clarification, I'm using Oracle 11g R2 and Java 6.

As detailed here and confirmed here, the default number of rows Oracle returns at time when querying for data over JDBC is 10. I am working on an app that to has to read and compare lots of data from our database. I thought that if we just increase defaultRowPrefetch to be something like 1000, then surely our app would perform faster. As it turned out, it performed slower and by about 20%.

We then decided to just slowly increase the number from 10 and see how it performs. We've seen about a 10% increase by setting it somewhere between 100 and 200. I would have never guessed, however, that setting it higher would make our app perform more slowly. Any ideas why this might happen?

Thanks!

EDIT:

Just for clarification, I'm using Oracle 11g R2 and Java 6.

EDIT 2:

Okay, I wanna restate my question to be clear, because judging from the answers below, I am not expressing myself properly:

How is it possible that if I set a higher fetch size, my app performs slower? To me, that sounds like saying "We're giving you a faster internet connection, i.e. a fatter pipe, but your web browsing will be slower.

All other things being equal, as they have been in our tests, we're super curious about how our app could perform worse with only this one change.

As detailed here and confirmed here, the default number of rows Oracle returns at time when querying for data over JDBC is 10. I am working on an app that to has to read and compare lots of data from our database. I thought that if we just increase defaultRowPrefetch to be something like 1000, then surely our app would perform faster. As it turned out, it performed slower and by about 20%.

We then decided to just slowly increase the number from 10 and see how it performs. We've seen about a 10% increase by setting it somewhere between 100 and 200. I would have never guessed, however, that setting it higher would make our app perform more slowly. Any ideas why this might happen?

Thanks!

As detailed here and confirmed here, the default number of rows Oracle returns at time when querying for data over JDBC is 10. I am working on an app that to has to read and compare lots of data from our database. I thought that if we just increase defaultRowPrefetch to be something like 1000, then surely our app would perform faster. As it turned out, it performed slower and by about 20%.

We then decided to just slowly increase the number from 10 and see how it performs. We've seen about a 10% increase by setting it somewhere between 100 and 200. I would have never guessed, however, that setting it higher would make our app perform more slowly. Any ideas why this might happen?

Thanks!

EDIT:

Just for clarification, I'm using Oracle 11g R2 and Java 6.