-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi,
Le 19 août 08 à 22:03, Robert Haas a écrit :
All database-driven applications have this problem. Any time you have a database on the backend and interface code on the front-end, you need to keep in mind that it won't necessarily be possible to update the two of them simultaneously, especially if you have multiple back-ends and multiple front-ends, as you almost certainly do. Even if PostgreSQL invalidated plans in the particular situation you're discussing, there would still be other problems. You could add a new, non-NULLable column to a table before updating the code that insert into that table, or drop an old column that the code still counts on being able to access.
Using functions the way Skype uses them means not issuing a single insert, update or delete directly from your code, but calling a function which takes care about it. So you use PostgreSQL transactionnal DDL to roll-out new function versions at the same time you push the schema modifications, and commit it all in one go.
Maybe in your particular environment plan invalidation for functions will solve most of the cases you care about
When the code only is a client to an SQL functions API, which effectively replaces SQL as the way to interact between code and database, then I believe plan invalidation at function change is the missing piece.
, but I respectfully submit that there's no substitute for good release engineering. If you don't know exactly what functions are going to be created, modified, or dropped on your production servers during each release before you actually roll that release out... you probably need to improve your internal documentation.
Agreed :) - -- dim -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (Darwin) iEYEARECAAYFAkirK2kACgkQlBXRlnbh1bmxvQCgmowpfnZ5nFRml0mNfj2HRE+3 HJEAnR3G6Lhnb7R4+iSze8xGACwyk4D7 =of1o -----END PGP SIGNATURE----- -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
