Thanks for answer,
Is it possible RewriteRules can save us ? Queries from application which uses views could be rewrited. (i have to study more deeply if it is possible with our views names). But will locks work correctly in this case ? Regards, Pierre Besson-Deblon -----Message d'origine----- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] la part de Emmanuel Cecchet Envoyé : 13 September 2007 00:28 À : Sequoia general mailing list Objet : Re: [Sequoia] oracle views Hi Pierre, > We use sequoia with oracle sgbd, > 2 applications are linked to sequoia, one uses TABLES and the other uses > VIEWS, some of this views are bidirectional (UPDATE statements are available) > > we succeed in starting controllers, requesting tables and views configuring a > static shema for the backend with a <DatabaseTable> markup for each table or > view of our schema. > > In an another hand i have seen Raidb1 level implies a table parsing. Though > the explanation his duplication needs to acquire locks on table when updates > are requested... > > 1) Is this interpretation correct ? > Yes. Note that this should also work without a static schema if you ask views to be fetched in your virtual database configuration file. > 2) Do we risk some database inconsistency with this configuration ? (If > first answer is yes, i'm afraid the second answer is yes too :( ) > If you are using Sequoia 2.x then yes, views are considered as separate tables. So if you update the view and try to access the tables, the proper locking will not be done. In Sequoia 3.x, it is possible to declare a view definition to tell which tables are accessed by a view so that Sequoia proceeds to the proper locking. However, it is my understanding that Sequoia 3.x will not be developed further nor supported. > 3) If this configuration is risky, what other choice do we have ? > As long as you always update data the same way (always through the view or always through the tables), you should be fine. Reads should be properly isolated with Oracle snapshot isolation whatever way you access them. If you are updating concurrently through the view and the tables, then you will have inconsistencies with Sequoia. Hope this helps, Emmanuel _______________________________________________ Sequoia mailing list [email protected] https://forge.continuent.org/mailman/listinfo/sequoia This mail has originated outside your organization, either from an external partner or the Global Internet. Keep this in mind if you answer this message. This e-mail is intended only for the above addressee. It may contain privileged information. If you are not the addressee you must not copy, distribute, disclose or use any of the information in it. If you have received it in error please delete it and immediately notify the sender. Security Notice: all e-mail, sent to or from this address, may be accessed by someone other than the recipient, for system management and security reasons. This access is controlled under Regulation of security reasons. This access is controlled under Regulation of Investigatory Powers Act 2000, Lawful Business Practises. _______________________________________________ Sequoia mailing list [email protected] https://forge.continuent.org/mailman/listinfo/sequoia
