Knut Anders Hatlen wrote: >" > > >I'll summarize my understanding of these two issues > > [snip very good explanation]
>As you suggested, the client could invoke the SQL directly. This would >however cause some problems: > > - if there is a bug in a metadata query, it is not enough to upgrade > the server, you would also have to upgrade all the clients. > > - if the server changes the name of a system table or a column in a > system table, old clients will be broken. > > > Another problem is that the metadata queries currently use non-supported syntax. Changing these to use supported syntax, such as Mamta did when adding optimizer directives would mean that the old non-supported syntax would have to stay in the server. One more thing not mentioned here was that Satheesh for 1120/1124 added some version dependent metadata queries, which were necessary for soft upgrade because with the full v10.2 upgrade, system columns needed to be accessed for the metadata queries that were not available on soft upgrade. That seemed like a reasonable approach to soft upgrade. Once all the infrastructure gets firmed up, it would be good to have some information on the Wiki about how maintain metadata queries. It is good to see it getting addressed. Kathey
