Question

This seems too straightforward as first to be a problem – but here is is anyway.

Lets say you have a search form, and you’re looking for companies which deal in certain branches of an industry. The form will present a set of set of checkboxes for each question, and the user may choose any amount they want.

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What are your favorite colors?

[ ] Red

[ ] Blue

[ ] Yellow

What are your favorite fruits?

[ ] Apple

[ ] Orange

[ ] Banana

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Problem No.1

If the user checks red and blue – do we pull from the database rows that match only both? Or do we include rows that also match just red or just blue? In my mind the end-user may expect to see one outcome or the other, or both!

Problem No.2

Baring in mind that the CMS I have to use stores data in arrays for each question. So Company A for the first question may hold values “Red|Blue” or “Red” or “Red|Blue|Yellow” etc – plus the fast that the form I have has 10 categories each with at least 5 checkboxes – how can I translate this into an efficient and optimised query without having to resort to if/else mish mash?

Any help much appreciated.

Answer 1

1. It’s very likely to be a conjunction (red or blue) not a disjunction (red and blue),, but it depends on the semantics of the question. If you give options that can co-occur, then you might need a disjunction.

2. I can’t see a better way than something like

   $colours = $POST[“colour[]”];
   $items = array();

   foreach ($colours as $colour) {

   $items[] = “‘$colour’ IN colours”;

   }

   $SQL .= “AND (“.implode(‘ OR ‘, $items).”)”;