Hi, Every once in a while when using a UNION query I get an exception that looks like this: !UNION: column counts (3 and 2) do not match (the numbers '3' and '2' vary from case to case) The message isn't right, because the queries I run do have matching column counts between the Unions. This happens to me in various scenarios. The thing that is common to all the cases is that it seems to happen when some sort of threshold is passed. For example, I can have a working query with 50 OR clauses in the WHERE statement that works, but as soon as I add the 51th OR clause, I get the exception. In other cases I get the same exception with a different amount of OR clauses, but again I see the behavior of the exception appearing when adding one more OR clause to a working query. The thing that is in common to all the failing queries is that there's always a join on two tables and I get data from both tables with a lot of OR clauses. If necessary I can upload data and queries that illustrate this, but the queries are rather long. Please advise. Thanks. -- View this message in context: http://old.nabble.com/strange-UNION-exception-tp26421401p26421401.html Sent from the monetdb-users mailing list archive at Nabble.com.