Posting the code and the table creation and populating scripts enables us to execute the code to see what is wrong. By withholding the above, you force the forum members to do more work - you do want a TESTED solution, don't you ?
Especially when you give an idea of the test data, it becomes easier to check if are cases not taken into account that could make your code fail.
So you can understand why we give so much importance to the code and data, it really is the best way to do things.