Compare table1 to table2

[jepatte]

I have a Table1 with 3 fields, lastname, firstname, zipcode

Table2 has the same. I want to insert records into Table1 if they are in Table2 but not already in Table1.

So is the best way to see if they exist is do a concatenation....

INSERT INTO T1 (LName, FName, Zip)
SELECT LName, FName, Zip FROM T2 WHERE LNAme + FName + Zip NOT IN (SELECT LName + FName + Zip FROM T1)

Is this the only way to do this?

 

[mrdenny]

You would want to use an EXISTS query for this.

insert into t1
select *
from t2
where NOT EXISTS (SELECT * from t1 where t1.LName = t2.LName and t1.FName = t2.FName and t1.Zip = t2.Zip)

Denny
MCSA (2003) / MCDBA (SQL 2000) / MCTS (SQL 2005) / MCITP Database Administrator (SQL 2005)

--Anything is possible. All it takes is a little research. (Me)

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