SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    447, 840, 445, 423, 426, 455, 430, 465, 
    466, 855, 832, 874
  )

Query time 0.00044

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_categories range parent parent 3 17 Using index condition

Result

category_id parent_id
445 423
426 423
455 423
465 423
466 423
855 423
447 430
845 832
840 832
875 874