Question : How to write a SQL statement in Sybase stored procudure with a condition in a where clause based on another condition?

I need incorporate a search from the front end which is being developed in coldfusion into a stored proc.
presently they are using the sql select statement.

Say I have a query
SELECT *
FROM A, B
WHERE A1 = @B1
AND A2 = @B2
AND A3 = @B3

presently the last two AND conditions are in the loops.

I need to incorporate this SQL into a stored procedure such that

if some condition say ( IF A2 or B2 if defined or has a value) Only then use the condition in the above select
statement-- (AND A2 = B2)otherwise dont use that particular condition.

i am prettly new to Sybase and could not find a solution on how to handle this.

Can anybody help me with this please?

Thanks,
Aeddy

Answer : How to write a SQL statement in Sybase stored procudure with a condition in a where clause based on another condition?

I assume what you mean is not if "A2 or @B2 is defined or has a value" but more like...
"If @B2 and/or @B3 is defined or has a value" then include the corresponding selection argument.

There are a couple of ways to do this. You can use traditional Boolean logic or you can use CASE statements in the WHERE clause. Either method works and you can see them in the code snippet.

Regards,
Bill

                       
             SELECT *
FROM A, B
WHERE A1 = @B1
AND (isnull(@B2,'') = '' OR A2 = @B2)   -- use on string values
AND (@B3 IS NULL OR A3 = @B3)    -- use on numeric and datetime values
 
SELECT *
FROM A, B
WHERE A1 = @B1
AND A2 = (CASE WHEN ISNULL(@B2,'') = '' THEN A2 ELSE @B2 END)
AND A3 = (CASE WHEN @B3 IS NULL THEN A3 ELSE @B3 END)

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