INSERT INTO inventory (id1,id2,quantity,type,char_name)
VALUES (
        (SELECT ('inventory'.'id'+1) AS 'free_id' FROM inventory
          WHERE (SELECT 1 FROM inventory AS st 
          WHERE st.id = ('inventory'.'id'+1))
          IS NULL ORDER BY 'inventory'.'id'+1
          LIMIT 1),
         %2,
         1,
         %5,
         '%1'
        )
WHERE (SELECT stackable FROM item 
       WHERE id = %2) = true AND 
      (SELECT money FROM character
        WHERE name = '%1') ›= 
      (SELECT costBay FROM item
        WHERE id = %2)AND
      (SELECT EXISTS(
       SELECT itemId
       FROM inventory
       WHERE itemId = %2 AND char_name = '%1'
       LIMIT 1)) = 0;