SELECT 
  * 
FROM 
  cscart_product_options_exceptions 
WHERE 
  product_id = 522 
ORDER BY 
  exception_id

Query time 0.00022

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_options_exceptions ref product product 3 const 1 Using where; Using filesort

Result

exception_id product_id combination
4293 522 a:3:{i:1359;s:5:"24265";i:752;s:2:"-1";i:753;s:5:"23604";}