Стас Денсис

Решение, может кому то поможет
В моем случае названия таблиц отличается от тех что в вопросе.

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SELECT
  master_products.id,master_products.name,master_product_regions.master_product_id AS mpr_id 				
FROM
  master_products

JOIN master_product_categories  on master_products.id=master_product_categories.master_product_id
			
 LEFT JOIN  master_product_regions    ON  master_products.id=master_product_regions.master_product_id
 WHERE
	  master_product_categories.category_id=803
  AND 
			(  
			   master_product_regions.id is NULL 
			   OR (master_product_regions.city_id = ".$city." AND master_product_regions.can_be_sold = 1)
			   OR (master_product_regions.city_id != ".$city." AND master_product_regions.can_not_be_sold=1)
		        )