Question

Blockquote

DECLARE @Symbol nvarchar(50);
DECLARE @EnDate1 Datetime;
DECLARE @StDate1 Datetime;
SET @Symbol = 'RIM12f'
SET @EnDate1 = '05/08/2012 9:00'
SET @StDate1 = '05 / 07 / 2012 12 : 00'
SELECT  *
FROM   Siri
WHERE (DATEADD(D, 0, DATEDIFF(D, 0, Date)) BETWEEN @StDate1 AND @EnDate1)
  AND  CASE Symbol = WHEN @Symbol = 'ALL'
                     THEN Symbol
                     ELSE Symbol LIKE LEFT(@Symbol, len(@Symbol) - 3) + '%'
       END

it does not works as same but
it works with else @Symbol
but i need all symbols like LEFT(@Symbol, len(@Symbol) – 3) + ‘%’ if @Symbol other than all

Answer 1

Modify you Case expression:

 Symbol LIKE CASE @Symbol WHEN 'ALL'
                     THEN Symbol
                     ELSE LEFT(@Symbol, len(@Symbol) - 3) + '%'