SQL Case Statement

CASE Statement example

SELECT

'Title' =
CASE TITLEOFCOURTESY
WHEN 'MS.' THEN 'MISSUS'
WHEN 'MRS.' THEN 'MISTRESS'
WHEN 'MR.' THEN 'MISTER'
WHEN 'DR.' THEN 'DOCTOR'
ELSE ''
END,
TITLEOFCOURTESY,
FIRSTNAME,
LASTNAME
FROM EMPLOYEES 

Output:

Title	TitleOfCourtsey	FirstName	LastName
Missus	Ms.	Nancy	Davolio
Doctor	Dr.	Andrew	Fuller
Missus	Ms.	Janet	Leverling

Example when the case input and output column is same, then use below query

SELECT PartId,

CASE Partcode WHEN 'AM102' THEN '1'

ELSE 'NULL'

END Code,

CtNumber FROM MySource.dbo.Inventory