Patent attributes
A computer system receives a database query to be executed against a database having a database table that stores records associated with keys. The database query specifies a set of conditional expressions that affect which ones of those records are returned. Based on the set of conditional expressions, the computer system derives a set of key ranges. The deriving can include representing the set of conditional expressions as a set of key spaces, performing a set of logical operations on pairs of those key spaces to reduce a number of key spaces in the set of key spaces, and converting the set of key spaces into the set of key ranges after performing the set of logical operations.