[PHP PDO Error 42000]

Message:	SQLSTATE[42000]: Syntax error or access violation: 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 ') OR r.ref_id IN ()) ORDER BY p.prdnam' at line 15
Code:	42000
File:	/home/jdplantservices/public_html/admin/patchworks.php
Line:	37
Trace:	0# file: /home/jdplantservices/public_html/admin/patchworks.php 0# line: 37 0# function: execute 0# class: PDOStatement 0# type: -> 0# args: 0: Array 1# file: /home/jdplantservices/public_html/admin/system/classes/related.cls.php 1# line: 117 1# function: run 1# class: db 1# type: -> 1# args: 0: SELECT r.rel_id, r.tblnam, r.tbl_id, r.refnam, r.ref_id, r.reltyp, p.prdnam, p.seourl, tp.prdnam AS thisname, tp.seourl AS this_seo FROM related r INNER JOIN products p ON r.ref_id = p.prd_id INNER JOIN products tp ON r.tbl_id = tp.prd_id WHERE TRUE AND r.tblnam = :tblnam AND r.refnam = :refnam AND (r.tbl_id IN () OR r.ref_id IN ()) ORDER BY p.prdnam 1# args: 1: Array 1# args: 2: 2# file: /home/jdplantservices/public_html/pages/custom/custom-product.php 2# line: 124 2# function: relatedProducts 2# class: RelDAO 2# type: -> 2# args: 0: 2# args: 1: PRODUCT 2# args: 2: 2# args: 3: PRODUCT 2# args: 4: 2# args: 5: 2# args: 6: RAND() 2# args: 7: 1

ERROR: SQLSTATE[42000]: Syntax error or access violation: 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 ') OR r.ref_id IN ()) ORDER BY p.prdnam' at line 15