Comments on: SQL SERVER – Transaction and Local Variables – Swap Variables – Update All At Once Concept

By: dURGESH

dURGESH — Sat, 05 Sep 2009 18:52:21 +0000

DECLARE @A INT, @B INT
SELECT @A=1,@B=2
SELECT @A A,@B B
SELECT @A=@A+@B,@B=@A-@B,@A=@A-@B
SELECT @A A,@B B

Madhivanan — Mon, 03 Nov 2008 13:57:18 +0000

For valriable swappings, you dont need a temp variable

DECLARE @VarA INT
DECLARE @VarB INT
DECLARE @VarTemp INT

SET @VarA = 1
SET @VarB = 2

SELECT @VarA =@VarA +@VarB,@VarB=@VarA- @VarB,@VarA=@VarA-@VarB

SELECT @VarA VarA, @VarB VarB

Paris — Sat, 01 Nov 2008 23:33:02 +0000

always ur articles r usefule .. merci ;)

Jerry Hung — Mon, 20 Oct 2008 19:21:06 +0000

This behaviour will be what I expected, thank god
being ATOMIC

For example
UPDATE table
SET column = GETDATE()

All columns obtain the same GETDATE() value, instead of milliseconds apart for a large table