select s.sectionName
     , i.itemId
     , i.itemName
     -- other inventoryItem columns as needed
     , p1.price
     , "sale_price" = p2.price
  from section s left join inventoryItem i 
        on s.sectionId = i.sectionId 
    left join itemPrice p1 
        on i.itemId = p1.itemId and p1.type = 0 
    left outer join itemPrice p2 
        on p1.itemId = p2.itemId and p2.type = 1 
       and p2.fromDate < getdate() and p2.toDate > getdate()