Question

i have three checkboxs in my application. If the user ticks a combination of the boxes i want to return matches for the boxes ticked and in the case where a box is not checked i just want to return everything . Can i do this with single SQL command?

Answer 1

You can build a SQL statement with a dynamic where clause:

string query = "SELECT * FROM TheTable WHERE 1=1 ";
if (checkBlackOnly.Checked)
    query += "AND Color = 'Black' ";
if (checkWhiteOnly.Checked)
    query += "AND Color = 'White' ";

Or you can create a stored procedure with variables to do this:

CREATE PROCEDURE dbo.GetList
    @CheckBlackOnly bit
,   @CheckWhiteOnly bit
AS
SELECT *
FROM TheTable
WHERE
    (@CheckBlackOnly = 0 or (@CheckBlackOnly = 1 AND Color = 'Black'))
    AND (@CheckWhiteOnly = 0 or (@CheckWhiteOnly = 1 AND Color = 'White'))
    ....