Hi, I am still learning about monetdb internals, so I hope someone can enlighten me here. I was playing around with monetdb, and run into the following problem: Suppose we have a table CREATE TABLE test.simple_table("id" INTEGER); INSERT INTO test.simple_table VALUES (1),(2),(3),(4),(5); Let's say I want to run a simple query: SELECT COUNT(*) AS val FROM test.simple_table ORDER BY val DESC; +----+ | v | +==+ | 5 | +----+ Runs fine. However, if add a *LIMIT* clause: SELECT COUNT(*) AS val FROM test.simple_table ORDER BY val DESC LIMIT 5; I get the following TypeException:user.s37_7[17]:'algebra.markT' undefined in: _30:any := algebra.markT(_27:oid, _29:oid) program contains errors Now things let's add a primitive *HAVING* clause SELECT COUNT(*) AS val FROM test.simple_table HAVING 1 > 0 ORDER BY val DESC LIMIT 5; +----+ | v | +==+ | 5 | +----+ And things are magically fine again. Can someone explain what's going on? Thanks, George Ramonov UC Berkeley B.S. Electrical Engineering & Computer Science '13 http://www.linkedin.com/in/georgeramonov