Re: Order by email address
От | Josh Berkus |
---|---|
Тема | Re: Order by email address |
Дата | |
Msg-id | web-54252@davinci.ethosmedia.com обсуждение исходный текст |
Ответ на | Re: Order by email address ("Josh Berkus" <josh@agliodbs.com>) |
Список | pgsql-sql |
Herve, Etc. Ooops! A couple of misteaks in that last post: > > toto@aol.com > > tutu@aol.com > > toto@be.com > > tutu@be.com > > toto@yahoo.com > > > > Is it possible and how ? > > Given the relational rule of Atomicity (each discrete piece of > information shall have its own column or row), the solution is for > you > to make "e-mail id" and "domain" seperate fields. Then you can sort: > > ORDER BY mailbox, domain I meant:ORDER BY domain, mailbox > > If this is a legacy database, and splitting the field is not an > option > for you due to exisiting applications/policy, then you'll need to > write > a custom sorting function: > > CREATE FUNCTION email_sort (VARCHAR) > RETURNS CHAR(120) AS ' > DECLARE > email_addr ALIAS for $1; > mail_box CHAR(60); > mail_domain CHAR(60); > BEGIN > mail_box := CAST(SUBSTR(email_addr, 1, (STRPOS(email_addr, ''@'', 1) > -1)) AS CHAR(60)); > mail_domain := CAST(SUBSTR(email_addr, (STRPOS(email_addr, ''@'', 1) > + > 1), 60) AS CHAR(60)); > RETURN mail_box || mail_domain; I meant:RETURN mail_domain || mail_box; > END;' > LANGUAGE 'plpgsql'; > > Then: > > SELECT user_id, email, email_sort(email) as sortcol > FROM users > ORDER BY sortcol; > -Josh ______AGLIO DATABASE SOLUTIONS___________________________ Josh Berkus Complete informationtechnology josh@agliodbs.com and data management solutions (415) 565-7293 for law firms, small businesses fax 621-2533 and non-profit organizations. San Francisco
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