Ivo Petkov wrote:
Hi all,
I have the following question:
As Derby does not support the SQL Limit (
http://mail-archives.apache.org/mod_mbox/db-derby-dev/200411.mbox/[EMAIL PROTECTED]
<http://mail-archives.apache.org/mod_mbox/db-derby-dev/200411.mbox/[EMAIL PROTECTED]>)
and
if I use java.sql.Statement.setMaxRows(X), does Derby stops scanning
the tables when X rows are found, or it the statement just
programatically limits the returned rows to X.
We have performance issues for a complex select query and we want to
limit the scanning of the database for example - only to the first 10
found rows.
With other words - Does Derby have such an optimization to stop
scanning the database when the first X results are found?
Regards,
Ivo
Hi -
This article addresses the issue of browsing large tables with Derby:
http://www.onjava.com/pub/a/onjava/2007/01/31/tuning-derby.html
Based on what I see in the Derby API it seems the answer depends on the
driver you are using:
Class EmbedStatement
setMaxRows
public void *setMaxRows*(int max)
throws java.sql.SQLException
The maxRows limit is set to limit the number of rows that any ResultSet
can contain. If the limit is exceeded, the excess rows are silently dropped.
HTH
