SELECT 
  v.variant_id, 
  v.product_id, 
  vd.variant, 
  vf.position, 
  vf.color 
FROM 
  cscart_product_features_values v 
  LEFT JOIN cscart_product_feature_variant_descriptions vd ON v.variant_id = vd.variant_id 
  AND vd.lang_code = 'en' 
  LEFT JOIN cscart_product_feature_variants vf ON v.variant_id = vf.variant_id 
WHERE 
  1 
  AND v.feature_id = 1536 
  AND v.product_id IN (
    '69929', '69933', '69932', '69934', 
    '69935', '69936', '69937', '69938', 
    '69939', '69940', '69941', '69942', 
    '69943', '69944', '69945', '69946', 
    '69947', '69948', '69949', '69950', 
    '69951', '69952', '69953', '69954', 
    '69967', '69968', '69969'
  )

Query time 0.00161

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "24.82"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "v",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "feature_id",
            "product_id"
          ],
          "key_length": "6",
          "rows_examined_per_scan": 27,
          "rows_produced_per_join": 27,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "3.22",
            "eval_cost": "2.70",
            "prefix_cost": "5.92",
            "data_read_per_join": "20K"
          },
          "used_columns": [
            "feature_id",
            "product_id",
            "variant_id"
          ],
          "attached_condition": "((`cscartdb`.`v`.`feature_id` = 1536) and (`cscartdb`.`v`.`product_id` in ('69929','69933','69932','69934','69935','69936','69937','69938','69939','69940','69941','69942','69943','69944','69945','69946','69947','69948','69949','69950','69951','69952','69953','69954','69967','69968','69969')))"
        }
      },
      {
        "table": {
          "table_name": "vd",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id",
            "lang_code"
          ],
          "key_length": "9",
          "ref": [
            "cscartdb.v.variant_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 27,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "6.75",
            "eval_cost": "2.70",
            "prefix_cost": "15.37",
            "data_read_per_join": "81K"
          },
          "used_columns": [
            "variant_id",
            "variant",
            "lang_code"
          ]
        }
      },
      {
        "table": {
          "table_name": "vf",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id"
          ],
          "key_length": "3",
          "ref": [
            "cscartdb.v.variant_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 27,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "6.75",
            "eval_cost": "2.70",
            "prefix_cost": "24.82",
            "data_read_per_join": "30K"
          },
          "used_columns": [
            "variant_id",
            "color",
            "position"
          ]
        }
      }
    ]
  }
}