Hello 2012/12/4 Edson Richter <edsonrichter@xxxxxxxxxxx>: > Em 04/12/2012 18:49, Sergey Konoplev escreveu: > >> On Tue, Dec 4, 2012 at 5:57 AM, Edson Richter <edsonrichter@xxxxxxxxxxx> >> wrote: >>> >>> In this specific case, the full length (14) is mandatory... so seems >>> there >>> is no loss or gain. >>> Also, I see all varchar(...) created are by default "storage = EXTENDED" >>> (from "Pg Admin"), while other datatypes (like numeric, smallint, >>> integer) >>> are "storage = MAIN". >>> Can I have a gain using fixed length datatype in place of current varchar >>> (like "numeric (14,0)")? >>> Or changing to "char(14) check length(doc)=14" and "storage=MAIN"? >> >> May be I am late with my reply but I would also recommend to take into >> consideration the article from depesz where he explains and tests all >> the textual types >> http://www.depesz.com/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/. >> >> Very useful one. > > > Yes, good education as well. I've read, and I'll consider the different > datatypes and more domain use in future. > > But I don't see much changes in our schema, so using varchar(14) seems to be > as good as text. > > My experience with other databases (MS SQL Server and Oracle) seems to not > apply 1:1 here (I've studied MSSQL internals and - at least up to 2005 > version - is much more efficient with char than with varchar than with text > - for all operations). sure - PostgreSQL has different design than "older" SQL servers that was developed for fixed length records. So some knowledges related to these databases are wrong here. Regards Pavel Stehule > > Thanks again, > > Edson > > > >> >> -- >> Sergey Konoplev >> Database and Software Architect >> http://www.linkedin.com/in/grayhemp >> >> Phones: >> USA +1 415 867 9984 >> Russia, Moscow +7 901 903 0499 >> Russia, Krasnodar +7 988 888 1979 >> >> Skype: gray-hemp >> Jabber: gray.ru@xxxxxxxxx >> >> > > > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
