Question

I am fairly new with PDO but i have come across something which probably has an easy answer.

I have an array of category numbers to which i need to search through a mysql database to find all items with the matching category number.

I know i have connected to DB correctly as i am receiving the category array from a different query.

$category = Array ( [0] => 3259 [1] => 3617 [2] => 3257 [3] => 3258 [4] => 3450 [5] => 3452 [6] => 3478 [7] => 3479 [8] => 3480 [9] => 3448 [10] => 3449 [11] => 3451 [12] => 3456 [13] => 3454 [14] => 3455 [15] => 3459 [16] => 3460 [17] => 3458 [18] => 3453 [19] => 3461 [20] => 3462 [21] => 3457 [22] => 3463 [23] => 3447 ) 

now i need to go through the item database to check for matching categories.
Each item can have multiple categories, each category has 4 digits.
multiple categories are seperate with a =

$categoryResults = $conn->prepare('SELECT * FROM items WHERE category like :cats ORDER BY promotions,price ASC');
$categoryResults->execute(array(':cats' => '%'.$category.'%'));
$categoryNumber = $categoryResults->rowCount();

This is where i seem to have gone wrong. With the mysql request i would have built it up manually using a loop through the array to get me a long sql query :

'Select * From items WHERE category like '%3259%' OR WHERE category LIKE '%3617%'........etc

But i am sure this is one of the advantages of using PDO.
Just to add to it i need the results to be unique.
If item 97 is in category 3259 and category 3617 i only want to get the result once.

Thanks in advance.

Answer 1

I find it stange that you are looking for numbers with a LIKE statement. Isnt category just the ID of the category or how is it stored? If category is CSV list, I advise you to alter it to make use of a seperate table for many to many connections.

If it’s already a numeric value, just use the IN statement

$categoryResults = $conn->prepare('SELECT * FROM items WHERE category IN (:cats) ORDER BY promotions,price ASC');
$categoryResults->execute(array(':cats' => implode(',', $category));
$categoryNumber = $categoryResults->rowCount();

Update
Or even better, check out this question which is the same.

Can I bind an array to an IN() condition?