Question

I need some guidance to make an advanced search script for a website I’m working on.

I already know how to search the database for simple queries. The problem I’m encountering right now is how to search, when using multiple select boxes. For example:

This is just a simple form with different search options. The question is:

The visitor can choose to search on a country or city, both or even with all three options.

How do I catch that in the PHP script? Do I have to check if for example a city has been chosen, and fire a query based on that? But if I do that I would have to make different queries based on each select option.

In pseudo-code it would be something like this: (I imagine)

if country and city and something else is not null, launch a query to search in all three tables in the database.

But what to do when just the country has been chosen? Or just the city?

Is there a simple way to accomplish this?

Thanks in advance.

Answer 1

I like using an array to join conditions so I don’t have to worry about leading or trailing AND’s.

$conditions = array();
if ($formCondition1) {
  $conditions[] = 'state = "'.$somevalue.'"';
}
if ($formCondition2) {
  $conditions[] = 'country = "'.$somevalue.'"';
}
...
if ($formConditionN) {
  $conditions[] = 'N = "'.$somevalue.'"';
}

//finally join the conditions together, the simplest case is with ANDs (if you need to add ORs, which it sounds like you don’t, then this code would be a bit more complex)

$sqlStatement = 'SELECT field1, field2 FROM tableABC WHERE '.implode(' AND ', $conditions);

EDIT: don’t forget to escape the input to prevent injection attacks, and of course test to make sure there are at least 1 condition before running the query.
EDIT: lol jswolf and I think very much alike 🙂