添加具有相同product_id的新字段后，数据会重复

I have two tables one called products the other product_images. product_images has 6 fields in this layout.

product_id, small_image, medium_image, large_image, width, height

small_image, medium_image and large_image are null fields.

My data has now duplicated after adding extra fields like small_image and large_image that have the same product_id.

My sql statement

"SELECT *,          
i.medium_image, i.width, i.height, 
    COALESCE((SELECT COUNT(*) 
    FROM order_details od 
    WHERE od.product_id = p.product_id), 0) as most_popular

FROM products p 
INNER JOIN product_images i on i.product_id = p.product_id
WHERE p.department_id=:department_id AND p.is_active=1
$orderby        
LIMIT :limit OFFSET :offset");

What do I need to do change my sql statement to only select the medium_image for the product so it won't duplicate, I tried using DISTINCT but that's not working. I just want to return the single product_image row that is medium_image related to the product_id

Try adding

GROUP BY product_id