RE: Problum Data type : Boolean on Informix

---------- From: Vira Ngramluxsameekhae[SMTP:ViraN@tac.co.th] Sent: Wednesday, February 04, 1998 2:45 AM Informix don't have boolean data type. JL: IUS does have a boolean data type, with constants T and F or 1 and 0. thus I have used dec(1) or char(1) in place of it . JL: OK. Both work. I know that size of dec(1) = 2 bytes and size of char(1) = 1 bytes which data type I should use and why. JL: Whichever works best for you. I'd use CHAR(1) with a CHECK constraint: CREATE TABLE WhatEver ( ... BoolCol CHAR(1) DEFAULT 'F' NOT NULL CHECK (BoolCol IN ('T', 'F')) CONSTRAINT we_boolcol1, ... ); This will be simplest to upgrade when you migrate to IUS or any other system with a boolean data type. If you want to allow '0' and '1' (for False and True respectively) instead, then that would work too; I'd still use a CHAR(1) column rather than a DEC(1) column, not only because the storage is smaller but also because the logic is (in my view) simpler. Your mileage may vary! Yours, Jonathan Leffler (jleffler@visa.com) #include <bother.ms-exchange.h>