Is there a reason you can't rewrite your SELECT like:
SELECT UUID FROM MDM.KEYWORDS_INFO WHERE KEYWORDS_ID IN (a, b, c, d)
Even doing them 100 at a time will make a big difference; you should
put as many in the list as pgsql supports. I'm assuming that there's
an index over KEYWORDS_ID.
Retrieving 10000 rows with 10000 statements is generally a Bad Idea.
S
At 08:17 AM 12/22/2005, Dave Cramer wrote:
The problem is you are getting the entire list back at once.
You may want to try using a cursor.
Dave
On 15-Dec-05, at 9:44 AM, johannesbuehler@xxxxxxxxxxxxxx wrote:
Hi,
I have a java.util.List of values (10000) which i wanted to use for
a query in the where clause of an simple select statement.
iterating over the list and and use an prepared Statement is quite
slow. Is there a more efficient way to execute such a query.
Thanks for any help.
Johannes
.....
List ids = new ArrayList();
.... List is filled with 10000 values ...
List uuids = new ArrayList();
PreparedStatement pstat = db.prepareStatement("SELECT UUID FROM
MDM.KEYWORDS_INFO WHERE KEYWORDS_ID = ?");
for (Iterator iter = ids.iterator(); iter.hasNext();) {
String id = (String) iter.next();
pstat.setString(1, id);
rs = pstat.executeQuery();
if (rs.next()) {
uuids.add(rs.getString(1));
}
rs.close();
}
...
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