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From: Stephen Quinn on 19 Nov 2009 09:19 }aul >> The field doesn't have to be in the index expression (of the chld) > of the master, you mean... ? No - the child Matter of fact it doesn't have to be in the expression of any index for the relationship to work. The only requirementa are that it's in both DBFs and the child has an index CYA Steve
From: Paul D B on 19 Nov 2009 10:07 Stephen Quinn wrote: > }aul > >>> The field doesn't have to be in the index expression (of the chld) >> of the master, you mean... ? > No - the child > > Matter of fact it doesn't have to be in the expression of any index > for the relationship to work. > The only requirementa are that it's in both DBFs and the child has an > index > CYA > Steve Are you sure Steve? I thought that the underlying mecanism was a seek. So the eacht time the master moves a record - a seek is performed in the child .. I don't see how you can seek on a common field when it is not incuded in the index expression of the child. See VO help for Setrelation:: As always, the child work area should have a controlling index that matches the expression." -- Paul
From: Johan Nel on 19 Nov 2009 12:32 Paul, SetRelation is not going to work for what you intend to do, except if you have a Str(InvCustNr, 6) + Descend(DToS(InvDate)) on the Invoice table. Then from the master: oCust:SetSelectiveRelation(oInv,; {|| Str(_FIELD->CustNr, 6, 0)},; "Str(CustNr, 6, 0)") HTH, Johan Nel Pretoria, South Africa. Paul D B wrote: > Stephen Quinn wrote: >> }aul >> >>>> The field doesn't have to be in the index expression (of the chld) >>> of the master, you mean... ? >> No - the child >> >> Matter of fact it doesn't have to be in the expression of any index >> for the relationship to work. >> The only requirementa are that it's in both DBFs and the child has an >> index >> CYA >> Steve > > Are you sure Steve? I thought that the underlying mecanism was a seek. So > the eacht time the master moves a record - a seek is performed in the child > . I don't see how you can seek on a common field when it is not incuded in > the index expression of the child. > > See VO help for Setrelation:: > As always, the child work area should have a controlling index that matches > the expression." > >
From: Geoff Schaller on 19 Nov 2009 16:29 You misunderstand. The index is in the child because this is where the seek occurs. You are confirming this. But the fields and the name does not have to be identical and the parent does not have to be indexed or even in the same order as the child. The only requirements are that the data type of the linked parent field and value has to match the index expression in the child. The child seek is triggered by a record movement in the parent. Don't forget you can relate on more than one field. Geoff "Paul D B" <polleke(a)NOMORESPAMhnt.be> wrote in message news:4b055f3e$0$2853$ba620e4c(a)news.skynet.be: > Stephen Quinn wrote: > > > }aul > > > > >>> The field doesn't have to be in the index expression (of the chld) > > >> of the master, you mean... ? > > > No - the child > > > > Matter of fact it doesn't have to be in the expression of any index > > for the relationship to work. > > The only requirementa are that it's in both DBFs and the child has an > > index > > CYA > > Steve > > > Are you sure Steve? I thought that the underlying mecanism was a seek. So > the eacht time the master moves a record - a seek is performed in the child > . I don't see how you can seek on a common field when it is not incuded in > the index expression of the child. > > See VO help for Setrelation:: > As always, the child work area should have a controlling index that matches > the expression." > > > -- > Paul
From: Stephen Quinn on 19 Nov 2009 17:35
Paul Yeah - I'm wrong again, no idea what I'm typing these days<g> - glad I've given programming away, seems like it's time for me to retire from the ng. Sorry for the misinformation. CYA Steve |