Bugs in lazy loading of result sets in 2.4.0 RC3

Question

I have a simple query that goes like that
Extent rules = pm.getExtent (RefundRule.class, false);
Query qryRefundRules = pm.newQuery (rules);
qryRefundRules.setFilter("ruleNr >= 0");
Collection refundRules = (Collection) qryRefundRules.execute ();
"ruleNr" is the primary key of the table and is an int.
The generated SQL as something like "select ... from refrule where t0 >= ?"
(perfect)
BUG 1:
The Collection "refundRules" is always empty, even though there are records
with ruleNr >= 0.
After some experimenting I found that the program works as expected if I
disable lazy loading by setting "com.solarmetric.kodo.DefaultFetchThreshold"
to "-1".
BUG2:
The same query without the filter produces another problem
Extent rules = pm.getExtent (RefundRule.class, false);
Query qryRefundRules = pm.newQuery (rules);
Collection refundRules = (Collection) qryRefundRules.execute ();
Now refundRules.size() gets me the correct number of records (35). But
walking through the collection is is very slow and throws this exception
after 10 records are retrieved from the Collection:
javax.jdo.JDODataStoreException: java.sql.SQLException: java.io.IOException:
LNA session closed [code=0;state=null]
NestedThrowables:
java.sql.SQLException: java.io.IOException: LNA session closed
at
com.solarmetric.kodo.impl.jdbc.runtime.SQLExceptions.throwDataStore(SQLExcep
tions.java:23)
at
com.solarmetric.kodo.impl.jdbc.runtime.LazyResultList.instantiateRow(LazyRes
ultList.java:201)
at
com.solarmetric.kodo.impl.jdbc.runtime.LazyResultList.get(LazyResultList.jav
a:123)
at java.util.AbstractList$Itr.next(AbstractList.java:416)
at
com.solarmetric.kodo.runtime.objectprovider.ResultListIterator.next(ResultLi
stIterator.java:49)
at com.globalrefund.refundmanual.Writer.write(Writer.java:92)
at com.globalrefund.refundmanual.Export.main(Export.java:17)
NestedThrowablesStackTrace:
java.sql.SQLException: java.io.IOException: LNA session closed
at
com.pervasive.jdbc.lna.LNAStatement.extendedFetch(LNAStatement.java:559)
at
com.pervasive.jdbc.lna.InsensitiveResultCache.fetchNext(J:/comp/sdk/jdbc/pvj
dbc2/src/com/pervasive/jdbc/lna/InsensitiveResultCache.java:450)
at
com.pervasive.jdbc.lna.InsensitiveResultCache.relative(J:/comp/sdk/jdbc/pvjd
bc2/src/com/pervasive/jdbc/lna/InsensitiveResultCache.java:277)
at com.pervasive.jdbc.v2.ResultSet.next(ResultSet.java:758)
at com.p6spy.engine.spy.P6ResultSet.next(P6ResultSet.java:123)
at
com.solarmetric.datasource.ResultSetWrapper.next(ResultSetWrapper.java:71)
at
com.solarmetric.kodo.impl.jdbc.runtime.LazyResultList.instantiateRow(LazyRes
ultList.java:165)
at
com.solarmetric.kodo.impl.jdbc.runtime.LazyResultList.get(LazyResultList.jav
a:123)
at java.util.AbstractList$Itr.next(AbstractList.java:416)
at
com.solarmetric.kodo.runtime.objectprovider.ResultListIterator.next(ResultLi
stIterator.java:49)
at com.globalrefund.refundmanual.Writer.write(Writer.java:92)
at com.globalrefund.refundmanual.Export.main(Export.java:17)
Again setting "com.solarmetric.kodo.DefaultFetchThreshold" to "-1" cures the
problem
I use "com.solarmetric.kodo.impl.jdbc.DictionaryClass" =
"com.solarmetric.kodo.impl.jdbc.schema.dict.GenericDictionary" (because I am
testing against Pervasive.SQL)
No other parameter set (everthing default)
Regards,
Bernhard

Answer 1

Thanks! Let me know if you need further information.
Regards,
Bernhard
"Patrick Linskey" <[email protected]> schrieb im Newsbeitrag
news:atioc1$3s0$[email protected]..
Bernhard,
Sorry about the delay getting back to you. We've been busy getting 2.4.0
released. We'll look into the issue further later this week.
-Patrick
Bernhard Mandl wrote:
Does "no response" mean you did not read my post or that you are not
willing
to look into it?
Thanks,
Bernhard
"Bernhard Mandl" schrieb im Newsbeitrag
news:asam6g$1rl$[email protected]..
Abe,
the same program worked perfectly with 2.3.x, so you must have changed
something. I could try to send you a reproducable example, but it will
probably take me a few hours to reduce it to something that I can send.Will
you look into it if I send you instructions how to reproduce? You can
download an evaluation version of Pervasive.SQL from the Pervasive
site.
>>>
Regards,
Bernhard
"Abe White" schrieb im Newsbeitrag
news:as92h5$ban$[email protected]..
Lazy loading works great with other databases (try it out with
Hypersonic
or any other databases you have). Apparently Pervasive.SQL's JDBCdriver
is
giving back invalid information. Since we obviously can't fix that,
you
should just stick with the -1 setting for DefaultFetchThreshold.--
Patrick Linskey [email protected]
SolarMetric Inc. http://www.solarmetric.com