Hello, My question is about index usage when bitwise operations are invoked. Situation Context: --------------------------
Lets suppose we have 2 tables TBL1 and TBL2 as the following: TBL1 { ......... ; integer categoryGroup; // categoryGroup is declared as an index on TABL1 ......... ; } TBL2 { ......... ; integer categoryGroup; // categoryGroup is declared as an index on TABL2 ......... ; } By conception, I suppose that: - [categoryGroup] may hold a limited number of values, less than 32 values. - [categoryGroup] is of type integer => it means 4 bytes => 32 bits => 32 places available to hold binary '0' or binary '1' values. - [categoryGroup] is the result of an "OR bitwise operation" among a predefined set of variables [variableCategory]. We suppose that [variableCategory] is of type integer (=>32 bits) and each binary value of [variableCategory] may only hold a single binary '1'. Ex: variableCategory1 = 00000000000000000000000000000010 variableCategory2 = 00000000000000000000000000100000 variableCategory3 = 00000000000000000000000000001000 If [categoryGroup] = variableCategory1 | variableCategory2 | variableCategory3 =>[categoryGroup] = 00000000000000000000000000101010 Question: -------------- I have an SQL request similar to: SELECT ..... FROM TBL1, TBL2 WHERE <inner join between TBL1 and TBL2 is True> AND TBL1.CATEGORY & TBL2.CATEGORY <> 0 //-- where & is the AND bitwise operator Qst: 1/ IS the above SQL request will use the INDEX [categoryGroup] defined on TBL1 and TBL2 ? 2/ What should I do or How should I modify my SQL request in order to force the query engine to use an index ? (the already defined index or another useful index) Thx a lot