From: Jason L. W. <jwh...@jw...> - 2007-07-25 13:31:16
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Dmitry wrote: > Adriano dos Santos Fernandes wrote: > > > > What you mean in "this is accordingly to the SQL specification"? > > AFAIR, the spec allows table aliases in UPDATE and DELETE. > > In the spec, both UPDATE and FOR UPDATE contain a <column list> > syntactical element which is different from <column reference>. What if in the FOR UPDATE OF <column list> the statement has a self referencing table JOIN and similarly named columns are repeated? Does it expect you to individually alias the duplicate columns and then list the alias names for the columns in that <column list> in order to distinguish them? I much prefer the <column reference> because it allows the table alias to be taken into consideration which helps to distinguish which relation a column is a part of. Isn't it true that <column list> is a subset of <column reference>? Also, isn't it possible that a <column list> is actually a list of individual <column reference> items? Thanks for your time to help me better understand the correct terminology on this matter. Regards, Jason L Wharton |