Oracle Query Hint

Normally Oracle query hints will be written using /*+ ... */syntax. One day I spent many hours trying to figure out why one of my queries took forever to finish if I ran it from QlikView and took only a minute if I ran it from Oracle SQL Developer. Turned out that QlikView by default would strip out comments from SQL statement and treat /*+ ... */ as a comment.

This “feature” is discussed here.

Solution is easy – just use –+ syntax instead if you need to pass a query hint. Of course it is a very easy thing to forget!