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Delete records from one table which exist in another

In SQL Server 2008 R2, I'm trying to delete records from one table that match records in another table based on the values in 4 fields. I've tried:

DELETE TR.*
FROM dbo.tbl_Readings_Tanks as TR
INNER JOIN zz_Staging_Tanks
ON (TR.Reading_Type_ID = zz_Staging_Tanks.Reading_Type_ID)
AND (TR.Prod_ID = zz_Staging_Tanks.Prod_ID)
AND (TR.docDate = zz_Staging_Tanks.docDate)
AND (TR.Equip_ID = zz_Staging_Tanks.Equip_ID)

But this returns an error :

Incorrect syntax near '*' and underlines as indicated.

There is an unique index in tbl_Readings_Tanks on those 4 columns.

Shaun Kline

DELETE FROM tbl_Readings_Tanks 
WHERE EXISTS (
   SELECT 1 
   FROM zz_Staging_Tanks 
    WHERE Reading_Type_ID = tbl_Readings_Tanks .Reading_Type_ID 
         AND Prod_ID = tbl_Readings_Tanks.Prod_ID
         AND docDate = tbl_Readings_Tanks.docDate 
         AND Equip_ID = tbl_Readings_Tanks.Equip_ID)

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You can verify prior to deleting by changing the DELETE FROM to SELECT * FROM.

Phillip Burton

Change line 1 to DELETE TR

Zberteoc

Remove .* from the DELETE line.

You use * only to SELECT, in the case of DELETE or UPDATE you only specify the alias, in this case TR.

ASKER CERTIFIED SOLUTION

Jim Horn

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Zberteoc

(2) Deleting with a JOIN requires two FROM's, which sounds kinda hokey I know.

No it doesn't need 2 FROMs.

Dale Fye

ASKER

Zberteoc,

it gave me an incorrect syntax error without the 1st FROM

Dale Fye

ASKER

Thanks, Jim.

Precisely what I was looking for, and thanks for the explanation.

Jim Horn

Thanks for the grade. btw If you're doing a lot of Access to SQL conversion I have an article out there on Migrating your Access Queries to SQL Server Transact-SQL that's a grab bag of differences.

Dale Fye

ASKER

Thanks, Jim; I'll take a look.

I've been moving what was an Access BE to SQL Server so that I can pull data in from multiple data sources. I've used SQL Server as a backend before, but never when trying to merge data with different structures from multiple sources. It has been a trip learning how to deal with PIVOT and MERGE querys. I really like the functionality of the MERGE queries and am now working on one that includes an and clause, so the it only updates a record in the target table if that record has not already been manually edited.