SELECT 
  * 
FROM 
  cscart_product_feature_variants 
WHERE 
  variant_id IN (
    4790, 4778, 4766, 4807, 4763, 4783, 4773, 
    4776, 4780, 5163, 5164, 5179, 5180, 
    4862, 3096, 3095, 3097, 3098, 4981, 
    3099, 5139, 3100, 3101, 5074, 3103, 
    3104, 4974, 4983, 3085, 5063, 4915, 
    3087, 3686, 3088, 3089, 3092, 3093, 
    4922, 3094, 3084, 4904, 1870, 0
  )

Query time 0.00100

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_feature_variants",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["variant_id"],
          "rows": 43,
          "filtered": 100,
          "index_condition": "cscart_product_feature_variants.variant_id in (4790,4778,4766,4807,4763,4783,4773,4776,4780,5163,5164,5179,5180,4862,3096,3095,3097,3098,4981,3099,5139,3100,3101,5074,3103,3104,4974,4983,3085,5063,4915,3087,3686,3088,3089,3092,3093,4922,3094,3084,4904,1870,0)"
        }
      }
    ]
  }
}