troubleshooting Question

MySQL Finding Duplicates in a Normalized Database

Avatar of Jacob Leis
Jacob Leis asked on
6 Comments1 Solution177 ViewsLast Modified:
I need to find duplicate records based on the following query:

SELECT, p.first, p.last, a.address1,, a.postalcode1
FROM 	global_main.person p,
		global_main.person_address pa,
		global_main.address a
WHERE = pa.person_id
AND = pa.address_id

Obviously the id will be unique for each record.  What would constitute a duplicate would be matching data in the following columns:
- p.first
- p.last
- a.address1
- a.postalcode1

I've never done joins across tables to determine duplication for a query such as this.  What I would need returned would be a list of the lowest id column value for each duplicate instance.  There are cases where there are multiple 'duplicates'.  Any help will be greatly appreciated.  Thank you.
Naitik Gamit
Senior Software Developer

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