OK, I see the problem you are talking about here.
I'll add this to my list of things to watch out for.

Jason Wharton
CPS - Mesa AZ
http://www.ibobjects.com

----- Original Message -----
From: "Martijn Tonies" <m.tonies@...>
To: <ibobjects@yahoogroups.com>
Sent: Friday, March 08, 2002 6:08 AM
Subject: Re: [IBO] KeyLinks error


> Hi Jason,
>
> I quoted (part of) the original conversation below.
>
> ===
> ok - while writing this email - I did some debugging and I found where
> it went wrong... I think there's a bit of a combination of factors here...
>
> First, here's the DDL for the table that's giving the error:
>
> CREATE TABLE IA_REPORT_RELOAD
> (
> ID INTEGER NOT NULL,
> IA_REPORT_ID INTEGER NOT NULL,
> RELOAD_ID INTEGER,
> CONSTRAINT IA_REPORT_RELOAD PRIMARY KEY (ID)
> )
>
> Here's the statement that gives the problem:
>
> SELECT RELOAD_ID FROM IA_REPORT_RELOAD
>
>
> In the above table, you can see ID being the primary key column. In
> IBA_Dataset.IMP, the method
>
> function TIB_Dataset.GetKeyLinks: TIB_StringList;
>
> seems to be the error...
>
> In the below part some comments by me are added
>
> ===
> TableName := SysKeyRelation;
> if TableName <> '' then
> begin
> IB_Connection.SchemaCache.GetTableKeys( TableName, FKeyLinks );
> if KeyLinksExist then
> begin
> SQLSelectStr := UpperCase(
> StripLitsAndRounds(
> StripComments( SQLSelect.Text ), SQLDialect ));
> if Pos( '*', SQLSelectStr ) = 0 then
> for ii := 0 to FKeyLinks.Count - 1 do
> begin
> tmpStr := UpperCase( FKeyLinks.IndexNames[ii] );
> tmpPos := getLitSafePos( '.', tmpStr, 1 );
> if tmpPos > 0 then
> tmpStr := Copy( tmpStr, tmpPos + 1, MaxInt );
> {
> for employee, tmpStr will turn up EMP_NO - if I select FIRST_NAME,
> there's no way that pos(tmpStr, SQLSelectStr) = 0 -> so, keylinks
> get cleared, DB_KEY gets added
>
> But, for SELECT RELOAD_ID FROM IA_REPORT_RELOAD -
> tmpStr will become ID (PK column) and Pos(tmpStr, SQLSelectStr) gives
> pos > 0 ----> no keylinks clear, no DB_KEY added --> error...
>
> }
> if Pos( tmpStr, SQLSelectStr ) = 0 then
> begin
> FKeyLinks.Clear;
> Break;
> end;
> end;
> end;
> if not KeyLinksExist then
> begin
> FKeyLinks.Add( TableName + '.' + IB_RDB + IB_DB_KEY );
> FKeyLinksAreDBKEY := true;
> end;
> FKeyLinksAutoDefined := KeyLinksExist;
> end;
> ===
>
>
> So I guess I can conclude in saying that the Pos function isn't the best
way
> to test here. The error seems to happen when you have a primary key column
> (tmpStr) that has a name that's part of another column (SQLSelectStr) -
> because Pos will find it, it assumes that this is the keylink. Wrong...
But
> I cannot think of an easy way to change it yet :)
>
>
>
> ===
>
> Hope this helps,
>
>
> --
> Martijn Tonies
> InterBase Workbench - the developer tool for InterBase and Firebird
> http://www.interbaseworkbench.com
>
> Upscene Productions
> http://www.upscene.com
>
> "This is an object-oriented system.
> If we change anything, the users object."
>
>
> > I don't have any specific recollection. I would have to dig things up on
> it.
> >
> > Jason Wharton
> > CPS - Mesa AZ
> > http://www.ibobjects.com
>
> >
> >
> > > Hi Jason, Geoff,
> > >
> > > Some time ago, I reported an error with KeyLinksAutoDefine with a
> > > reproducable piece of DDL and so on...
> > >
> > > We had quite some discussion on how to do what and why and how to
solve
> > this
> > > error. I was wondering if there was any progress or talk about this
> error
> > in
> > > order to get to a solution for this problem.
> > >
> > > Thanks,
> > > --
> > > Martijn Tonies
> > > Upscene Productions
> > >
> > > InterBase Workbench - The Developer Tool for InterBase
> > > http://www.interbaseworkbench.com
> > >
> > > "Experience is what you get when you didn't get what you wanted"
> >
> >
> >
>
>
>
>
>
>
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