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Technical information on this site may be out of date : no updates since 2015

SQL Greatest and Least

July 21, 2009 , posted under postgresql mysql sql

Most of the time I can get what I want out of SQL using the standard aggregate functions, but today I needed to find the latest timestamp from any one of three columns.

I achieved this using the GREATEST() function, it’s not part of the SQL standard but is commonly available.

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Restoring an old Postgresql database

January 16, 2008 , posted under postgresql

I’ve just had cause to restore a two year old backup of a database I haven’t used in a whileSince then postgresql (on Debian at least) has added the option to have multiple ‘clusters’ and multple versions running on the same machine.

Fortunately the old version (7.4) was still available


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