Query to Determine First Day of the Week

[sarah]

Hello,

Can someone help me figure out a very fast query that can determine the date of the first day of the week (assuming Monday is the first day) for a given date?

For instance, for today, 03/21/2013 I would like to get Monday, 03/18/2013, as a result.

Thanks!

[Julie]

Sarah,

You are in luck! Vertica has a function to do that:

Code: Select all

dbadmin=> SELECT date_trunc('week', DATE '03/21/2013');
     date_trunc
---------------------
 2013-03-18 00:00:00
(1 row)

Refer to the post viewtopic.php?f=63&t=375&p=1189&hilit=date_trunc#p1189 for more examples that use the date_trunc function.

[sarah]

Thanks, Julie! That's perfect!