Abstract: A method, computer program, and computer network are disclosed for organizing values of multiple alternative equality conditions between a database column and a set of values. The method includes applying a function to each value to obtain a result for each value. The values are organized into groups where each group includes values with the same result. The values are stored according to the groups. A computer program or database system executes queries that include multiple alternative equality conditions between a database column and a set of values. The database system also includes an optimizer that is configured to apply a function to each value to obtain a result for each value. The values are organized into groups where each group includes values with the same result. The values are stored according to the groups.

Abstract: A method, computer program, database system and data structure for coding a compressible variable length field in a row to be added to a database table are disclosed. The row has a value to be stored in the compressible variable length field. The value is searched for in a list of values for the compressible variable length field stored in the table. IF the value is found in the list of values, the row is created in the table with a first code associated with the value, a second code associated with a location in the row, but without the compressible variable length field. Otherwise, the row is created in the table with the value stored in the compressible variable length field, a first code indicating that the value is stored in the row, and a second code associated with the location of the value in the row.