According to an aspect, a system for moving a filter in a query model to ensure query semantics includes a query engine configured to obtain a query model for a query to be executed on a database. The query engine includes a query optimizer configured to instantiate the query model by merging the query with the query model. The query optimizer includes a filter mover configured to move a filter to a point within the instantiated query model such that semantics for the query within the instantiated query model is ensured.