SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    422, 423, 424, 425, 426, 427, 428, 429, 
    3278, 3330
  )

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": ["parent"],
      "key": "parent",
      "key_length": "3",
      "used_key_parts": ["parent_id"],
      "rows": 87,
      "filtered": 100,
      "index_condition": "cscart_categories.parent_id in (422,423,424,425,426,427,428,429,3278,3330)"
    }
  }
}

Result

category_id parent_id
514 422
515 422
516 422
517 422
518 422
519 422
3493 422
3497 422
3499 422
490 423
491 423
492 423
493 423
494 423
495 423
496 423
497 423
498 423
539 423
3317 423
3318 423
3319 423
3320 423
3492 423
483 424
484 424
485 424
486 424
487 424
488 424
489 424
3313 424
3314 424
3315 424
3316 424
3366 424
3894 424
534 425
535 425
536 425
537 425
538 425
499 426
500 426
501 426
502 426
503 426
504 426
520 427
521 427
522 427
523 427
524 427
3321 427
3322 427
3323 427
3324 427
3491 427
525 428
526 428
527 428
528 428
529 428
530 428
531 428
532 428
533 428
3286 428
3287 428
3288 428
3289 428
3290 428
3494 428
505 429
506 429
507 429
508 429
509 429
510 429
511 429
512 429
513 429
3325 429
3326 429
3327 429
3328 429
3329 429
3495 429
3279 3278
3280 3278
3281 3278
3282 3278
3283 3278
3284 3278
3285 3278
3496 3278
3331 3330
3332 3330
3333 3330
3334 3330
3335 3330