OsCommerce is literally the most awful piece of software ever. Granted, I'm migrating a version from 2007, but even still.

The admin area has a screen to set related products to a target product.

The page takes an age to load, even longer to save and is god awful to use from a UI POV.

Why may you ask?

The OsCommerce devs decided to display a flat list, which check boxes of ALL products in the database.

So for the site in question, that's a single list of 167,000 products, without pagination. Some of the worst development/design on a single page I've seen since last week when I inherited a god awful butchered Wordpress site :|