Posted by Erland Sommarskog on 11/28/07 22:46

--CELKO-- (jcelko212@earthlink.net) writes:
> This should be a no-op, but it scrambles everything
>
> BEGIN
> DELETE FROM Foo
> WHERE server_name = 'server_bob';
> INSERT INTO Foo VALUES ('server_bob');
> END;
>
> And you added the cost of an extra index with the UNIQUE, too!

Why should that by necessity be a no-op? Say that the table definition is

CREATE TABLE Foo(server_name varchar(15) NOT NULL PRIMARY KEY,
addedwhen datetime NOT NULL DEFAULT CURRENT_TIMESTAMP);

--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server 2005 at
http://www.microsoft.com/technet/prodtechnol/sql/2005/downloads/books.mspx
Books Online for SQL Server 2000 at
http://www.microsoft.com/sql/prodinfo/previousversions/books.mspx

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