PHP search with few parameters - php

Question

I have an query that I am trying to do search with multiple parameters to sort my data response from sql.
The query code :
$sql = "SELECT * FROM `apartments` WHERE `building_num`='{$i}' ORDER by `apartment_num` ASC";
The search form :
<form method="GET">
<input type="hidden" name="page" value="price">
<select class="styled-select2" name="type">
<option value="0">Apartment type</option>
<option value="דופלקס">Duplex</option>
<option value="דירה">Apartments</option>
<option value="דירת גן">דירת גן</option>
</select>
<select class="styled-select2" name="rooms">
<option value="0">rooms</option>
<option value="4">4</option>
<option value="3">3</option>
<option value="5">5</option>
</select>
<select class="styled-select2" name="price">
<option value="0">Price</option>
<option value="700000-800000">700,000-800,000 ₪ </option>
<option value="800000-900000">800,000-900,000 ₪</option>
<option value="900000-1000000">900,000-1,000,000 ₪</option>
<option value="1000000-1100000">1,000,000-1,100,000 ₪</option>
<option value="1100000-1200000">1,100,000-1,200,000 ₪</option>
<option value="1200000-1300000">1,200,000-1,300,000 ₪</option>
<option value="1300000-1400000">1,300,000-1,400,000 ₪</option>
<option value="1400000">1,400,000 up</option>
</select>
<input type="hidden" name="action" value="search">
<button type="submit">Search</button>
</form>
There are three parameters but they are not required, could the customer only use 'apartment type' AND 'Price' OR only one parameter, I tried for few hours to write query with no success, Any one can help ?
// Vars on table apartments
// Rooms - > Rooms
// Price -> price
// Apartment type -> type

Answer 1

1st of all, there's no direct link between and query (or queries) and tge options you're giving to the customer...
If you want to then you can allow the customer to fill some of the fields and if you don't then no... it's a matter of decision, from which derives the development
There's missing example code, so I can obly answer regarding the query and add some remarks
Since you've given specific select options, then you should use it for specific searches
I would also use some validations on the $_POST information returned
Regarding the query, I need to assume that all of the options are saved in the apartments table, under that, then the query should be something like this :
$sql = "SELECT * FROM `apartments` WHERE
rooms = $rooms
OR `type` = $type
OR (price BETWEEN *$range_min* AND *$range_max*)
ORDER by `apartment_num` ASC";
If you want all parameters combined you should use AND instead of OR
and, again, you can decide you want both and use different queries for each scenario the user givea

Answer 2

In this case you have to build dynamic query as below :-
$sql = "SELECT * FROM `apartments` WHERE ";
$condition = "";
$condition .= ($rooms=='')?"":" or 'rooms'= $rooms ";
$condition .= ($type=='')?"":" or 'type'= $type ";
$condition .= ($price=='')?"":" or prince bewteen 'range_min' AND 'range_max'";
$sql .= $condition;
$sql .= " ORDER by `apartment_num` ASC";
In this way you can make all three filters free to select or not.