On Tue, Jul 15, 2003 at 03:15:58PM +0200, Michael Van Canneyt wrote: > > > On Tue, 15 Jul 2003, James Mills wrote: > > > On Tue, Jul 15, 2003 at 04:36:24AM -0700, Alan Mead wrote: > > > > > > --- James Mills <[EMAIL PROTECTED]> wrote: > > > > > > > Just reconfirming with you and solidifying my knowledge. > > > > The reason it returns "" is because: when working with > > > > native pascal types, assigning null to a string results > > > > in an empty string "" right ? > > > > > > > > cheers > > > > James > > > > > > James, > > > > > > Pascal is a strongly typed language and there is no Pascal string > > > precisely equivalent to a NULL. Someone (either the SQLite authors > > > or the one who wrote the Pascal wrapper) decided to automatically > > > translate NULL into empty (zero-length) strings. And it's impossible > > > now to distinguish actual null values from fields containing actual > > > zero-length strings. > > > > I think I'm slowly understanding this bit now. I don't claim to be an > > SQL expert. But SQL (sqlite anyway) is capable of storing any data > > types, strings, integers, boolean etc, including NULL values. I hope I'm > > correct here... > > > > I don't believe the authors of the sqlite unit do translate NULL into > > empty (zero-length) strings. I did check the source, check yourself if > > I'm wrong. > > They do. But implicitly, by converting a pchar to a string. A nil will > be converted to an empty string.
Oh :) It's funny how I haven't been able to actually reproduce this in some test programs on Linux using FPC. cheers James > > Michael. > > > _______________________________________________ > fpc-pascal maillist - [EMAIL PROTECTED] > http://lists.freepascal.org/mailman/listinfo/fpc-pascal -- - - James Mills Zero Defect Software Engineers Group - ZDSEG _______________________________________________ fpc-pascal maillist - [EMAIL PROTECTED] http://lists.freepascal.org/mailman/listinfo/fpc-pascal
