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QuestionHaving a bad SQL day Pin
TheComputerMan12-Feb-13 23:40
memberTheComputerMan12-Feb-13 23:40 
AnswerRe: Having a bad SQL day Pin
Jörgen Andersson13-Feb-13 0:20
memberJörgen Andersson13-Feb-13 0:20 
GeneralRe: Having a bad SQL day Pin
TheComputerMan13-Feb-13 0:32
memberTheComputerMan13-Feb-13 0:32 
GeneralRe: Having a bad SQL day Pin
Jörgen Andersson13-Feb-13 0:40
memberJörgen Andersson13-Feb-13 0:40 
GeneralRe: Having a bad SQL day Pin
Bernhard Hiller13-Feb-13 3:24
memberBernhard Hiller13-Feb-13 3:24 
GeneralRe: Having a bad SQL day Pin
TheComputerMan13-Feb-13 3:33
memberTheComputerMan13-Feb-13 3:33 
AnswerRe: Having a bad SQL day Pin
Shameel13-Feb-13 0:53
memberShameel13-Feb-13 0:53 
To add to Jorgen's answer, I've always wondered why SQL Server doesn't allow us to use alias in WHERE and HAVING clauses. The answer to that lies in the logical order in which the query is processed. The WHERE and HAVING clauses are processed before the SELECT clause and the alias do not exist at that stage.

However, technically it should be possible to introduce another stage earlier in the query processing pipeline where a mapping between expressions and their alias is made and WHERE and HAVING clauses can look up to these mappings and substitute the actual expression in place of the alias.
GeneralRe: Having a bad SQL day Pin
Jörgen Andersson13-Feb-13 0:56
memberJörgen Andersson13-Feb-13 0:56 
GeneralRe: Having a bad SQL day Pin
PIEBALDconsult13-Feb-13 4:01
memberPIEBALDconsult13-Feb-13 4:01 
GeneralRe: Having a bad SQL day Pin
Jörgen Andersson13-Feb-13 6:27
memberJörgen Andersson13-Feb-13 6:27 

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