Memory issues

I'm getting errors from Oracle about running out of memory (Can't allocate 512 bytes for ....). I don't have the exact text of the error and of my query with me right now, so this will be a little general.

The query itself only returns a single row, involves several joins (three self joins and joins to two other tables), but all the joins are on indexed primary key columns. The query is done by a java program and is called multiple times depending on the user's activity. The memory error only comes up when I do a bunch of queries in a row (something like 20 or 30). And then all subsequent queries give the error.

Because this happens only after multiple queries, it is as if there is a memory leak, or as if oracle is saving all the previous queries or something.

My current plans are to try this a stored procedure with bind variables. But does anyone have any ideas about why this would be happening? Is there something I can flush to fix this? My dba has been allocating more memory for me, but that hasn't helped.

Thanks.

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