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From: Andrew Gierth <andrew@tao11.riddles.org.uk>
To: Ertan =?utf-8?B?S8O8w6fDvGtvxJ9sdQ==?= <ertan.kucukoglu@1nar.com.tr>
Cc: pgsql-sql <pgsql-sql@lists.postgresql.org>,
 "David G. Johnston" <david.g.johnston@gmail.com>
Subject: Re: Converting from MySQL
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	(David G. Johnston's message of "Tue, 22 Jan 2019 14:42:25 -0700")
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 >> Failed to find PostgreSQL equivalent for below one because I did not
 >> understand what it does in the first place.
 >> 
 >> SELECT
 >> CONCAT(SUBSTRING_INDEX(email,'@',-1),'/',SUBSTRING_INDEX(email,'@',1),'/')
 >> FROM users WHERE email='%s'

It looks to me like this would work as well or better in PG:

select regexp_replace(email, '^(.*)@(.*)$', '\2/\1/') from ...

-- 
Andrew (irc:RhodiumToad)