HELP: How to tame the 8.3.x JDBC driver with a biq guery result set

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Hey folks

I am trying to do a full table scan on a large table from Java, using a straightforward "select * from foo". I've run into these problems:

1. By default, the PG JDBC driver attempts to suck the entire result set into RAM, resulting in java.lang.OutOfMemoryError ... this is not cool, in fact I consider it a serious bug (even MySQL gets this right ;-) I am only testing with a 9GB result set, but production needs to scale to 200GB or more, so throwing hardware at is is not feasible.

2. I tried using the official taming method, namely java.sql.Statement.setFetchSize(1000) and this makes it blow up entirely with an error I have no context for, as follows (the number C_10 varies, e.g. C_12 last time) ...

org.postgresql.util.PSQLException: ERROR: portal "C_10" does not exist
    at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:1592)
    at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1327)
    at org.postgresql.core.v3.QueryExecutorImpl.fetch(QueryExecutorImpl.java:1527)
    at org.postgresql.jdbc2.AbstractJdbc2ResultSet.next(AbstractJdbc2ResultSet.java:1843)

This is definitely a bug :-)


Is there a known workaround for this ... will updating to a newer version of the driver fix this?

Is there a magic incation of JDBC calls that will tame it?

Can I cast the objects to PG specific types and access a hidden API to turn off this behaviour?

If the only workaround is to explicitly create a cursor in PG, is there a good example of how to do this from Java?

Cheers
Dave






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