Listmail <lists@xxxxxxxxxx> writes: >> Any idea why using a variable v_streetName instead of a string 'wynn%' >> behaves differently? > Yeah. > 'wynn%' doesn't start with % so LIKE uses index. > But Postgres doesn't know that you know that the contents of this > variable never starts with '%'... Even more to the point: the transformation of LIKE 'pattern' into an index range is a plan-time optimization, so if the planner hasn't got a constant pattern to work with, it'll never happen. (Yeah, this should be improved someday.) If you need to depend on LIKE indexing with non-constant patterns, you'll have to use EXECUTE to force the query to be replanned each time. regards, tom lane
