"Gaetano Mendola" <[EMAIL PROTECTED]> writes: > Tom Lane wrote: > > > Gaetano Mendola <[EMAIL PROTECTED]> writes: > > > >>I think a warning is missing if I create a table without OIDS that > >>inherits from a table with oids: > > > > > >>don't you think a warning shall to be raised here ? > > > > > > Nope ... this is not different from the behavior for merging duplicate > > column definitions. You get an OID column if the child table definition > > *or* any parent table requests OIDs. > > Mmm, you are not convincing me, don't we break the principle of minor surprise? > > I mean if you duplicate a column name that column is present on the inherited > table, but if I say: I don't want the column OID and I found it, this then > surprise me. > Speaking in generic OO terms, using inheritance, you cannot remove attributes that are present in the generalisation. If B inherits A, an instance of B is per definition also an instance of A. Thus, you must alwasy be able to cast a B into an A. In short, If you don't want the OID, you cannot inherit a something that has an OID.
Having said that, I think a warning is motivated. The warning should state that attributes (columns) present in the generalisation (the parent table) cannot be hidden. Kind regards, Thomas Hallgren ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
