SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    982, 942, 947, 1030, 1009, 1062, 1006, 
    956, 1008
  ) 
  AND category_id != 414

Query time 0.00060

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.11"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "parent",
        "p_category_id"
      ],
      "key": "parent",
      "used_key_parts": [
        "parent_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 33,
      "rows_produced_per_join": 33,
      "filtered": "100.00",
      "index_condition": "(`s2cart`.`cscart_categories`.`parent_id` in (982,942,947,1030,1009,1062,1006,956,1008))",
      "cost_info": {
        "read_cost": "13.81",
        "eval_cost": "3.30",
        "prefix_cost": "17.11",
        "data_read_per_join": "116K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`s2cart`.`cscart_categories`.`category_id` <> 414)"
    }
  }
}

Result

category_id parent_id
943 942
944 942
945 942
946 942
948 947
949 947
950 947
951 947
957 956
958 956
959 956
960 956
961 956
962 956
963 956
983 982
984 982
985 982
986 982
987 982
988 982
989 982
1007 1006
1010 1009
1011 1009
1031 1030
1032 1030
1033 1030
1034 1030
1035 1030
1036 1030
1037 1030