SELECT 
  * 
FROM 
  cscart_product_options_inventory 
WHERE 
  product_id = 9842 
  AND combination_hash = '3364479105'

Query time 0.00023

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_options_inventory const PRIMARY,pc PRIMARY 4 const 1

Result

product_id product_code combination_hash combination amount temp position price weight min_qty max_qty qty_step list_qty_count aval_status
9842 ODV-DFD-C01-0705S 3364479105 955_18542_1154_21870_1155_21886 0.00 N 96 395.12 2.50 0 0 0 0 15