On Thu, Mar 19, 2009 at 11:50 AM, Scott Marlowe <scott.marlowe@xxxxxxxxx> wrote: > On Tue, Mar 17, 2009 at 5:25 AM, Juan Pereira > <juankarlos.openggd@xxxxxxxxx> wrote: >> Hello, >> >> The question is: Which DBMS do you think is the best for this kind of >> application? PostgreSQL or MySQL? > > Another advantage pgsql has is that many ddl operations on tables do > NOT require exclusive locks on those tables. Creating indexes, adding > / dropping columns in mysql will lock the whole table and adding > dropping columns will rewrite the whole table. In pgsql adding and > dropping columns is almost immediate, and you can create indexes > concurrently so that the table you're creating the index on is not > locked. This is a big deal on a large production system where index > creation could take anywhere from several minutes to several hours. > > Note that almost all ddl is transactable as well, so testing big > schema changes is much safer in pgsql, where you can rollback just > about anything except create / drop database / tablespace. > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general > This is the nicest feature about postgresql by far. It almost compensates the lack of in place upgrade. merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
