using if in sql server where clause

Vote count:

0

im trying to add a column in where clause in sql server2005, but issue is i have to add it for a given condition like

where condition  1
and condition 2
if(@val !=null and @val = 'test')
begin
and condition 3
end

but when i try this sql server gives me error:

Incorrect syntax near the keyword 'and'. Severity 15 Procedure Name
Incorrect syntax near 'END'. Severity 15 Procedure Name

i did some R&D and found that i should use case statement instead and then i tried this

where condition  1
    and condition 2
    CASE @val 
    WHEN 'test' THEN AND condition 3
END 

but now its giving error:

Incorrect syntax near the keyword 'CASE'. Severity 15 Procedure Name

can any one help me to sort out the problem thanks.

asked 37 secs ago

zzzz

2,383