Sunday, December 14, 2008

Power of SQL: Update Join Tables

This is one of the most common update queries I do when dealing with multiple tables that needs data updated.
update o
set o.status = 'complete'
from orders o
join order_detail od
on = od.order_id
where ... (criteria here)
I often see code that will do a select and then update the subsequent table where id in (list_of_values). Remember that (almost?) anytime you see an IN clause, it can be replaced with a more efficient join statement.

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