SELECT 
  * 
FROM 
  cscart_product_options_inventory 
WHERE 
  product_id = 10962 
  AND combination_hash = '1147022796'

Query time 0.00068

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
10962 ODR-EDZ-0507 1147022796 1318_23941_1319_23948 0.00 N 0 333.00 14.75 0 0 0 0 5