A PHP Error was encountered

Severity: Notice

Message: Undefined index: nid_material_products

Filename: controllers/product.php

Line Number: 156

A Database Error Occurred

Error Number: 1064

You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '' at line 1

SELECT * FROM vattudienpower_tmaterial_products as a WHERE a.nid is not null AND a.nid =