SELECT 
  * 
FROM 
  jmj_product_feature_variants 
WHERE 
  variant_id IN (
    3231, 3246, 3247, 1486, 1487, 1488, 1492, 
    1494, 1496, 1497, 1498, 1503, 1507, 
    1509, 1510, 1513, 1515, 1516, 1518, 
    1521, 1522, 1524, 1525, 1526, 1527, 
    1528, 1529, 1530, 1531, 1538, 1539, 
    2103, 2113, 2118, 2150, 2201, 2205, 
    766
  )

Query time 0.00247

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "91.21"
    },
    "table": {
      "table_name": "jmj_product_feature_variants",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "variant_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 38,
      "rows_produced_per_join": 38,
      "filtered": "100.00",
      "index_condition": "(`jmj_test`.`jmj_product_feature_variants`.`variant_id` in (3231,3246,3247,1486,1487,1488,1492,1494,1496,1497,1498,1503,1507,1509,1510,1513,1515,1516,1518,1521,1522,1524,1525,1526,1527,1528,1529,1530,1531,1538,1539,2103,2113,2118,2150,2201,2205,766))",
      "cost_info": {
        "read_cost": "83.61",
        "eval_cost": "7.60",
        "prefix_cost": "91.21",
        "data_read_per_join": "58K"
      },
      "used_columns": [
        "variant_id",
        "feature_id",
        "url",
        "color",
        "position",
        "abt__ut2_color_style",
        "abt__ut2_multicolor"
      ]
    }
  }
}