SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    3935, 1334, 1335, 1336, 1337, 1338, 1339, 
    1340, 1341, 1342, 1343, 1344, 1355, 
    1356, 1357, 1358, 1359, 1360, 1361, 
    1362, 1363, 1364, 3688, 3689, 3690, 
    3691, 3692, 3693, 3694, 3695, 3696, 
    3697, 3709, 3710, 3711, 3712, 3713, 
    3714, 3715, 3716, 3717, 3718, 3708, 
    3152, 25, 1365, 3138, 3149, 6719, 3146, 
    3150, 1345, 1346, 1347, 1348, 1349, 
    1350, 1351, 1352, 1353, 1354, 3698, 
    3699, 3700, 3701, 3702, 3703, 3704, 
    3705, 3706, 3707, 6723, 6717, 6720, 
    3151, 3864, 3145, 6721, 3863, 3148, 
    6718, 6722, 3144, 3147, 3096, 339, 3104, 
    3107, 6682, 6678, 104, 105, 106, 107, 
    108, 109
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00121

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "115.60"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 96,
      "rows_produced_per_join": 96,
      "filtered": "100.00",
      "index_condition": "((`gaseus`.`cscart_product_descriptions`.`product_id` in (3935,1334,1335,1336,1337,1338,1339,1340,1341,1342,1343,1344,1355,1356,1357,1358,1359,1360,1361,1362,1363,1364,3688,3689,3690,3691,3692,3693,3694,3695,3696,3697,3709,3710,3711,3712,3713,3714,3715,3716,3717,3718,3708,3152,25,1365,3138,3149,6719,3146,3150,1345,1346,1347,1348,1349,1350,1351,1352,1353,1354,3698,3699,3700,3701,3702,3703,3704,3705,3706,3707,6723,6717,6720,3151,3864,3145,6721,3863,3148,6718,6722,3144,3147,3096,339,3104,3107,6682,6678,104,105,106,107,108,109)) and (`gaseus`.`cscart_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "106.01",
        "eval_cost": "9.60",
        "prefix_cost": "115.61",
        "data_read_per_join": "438K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "meta_keywords",
        "meta_description",
        "search_words",
        "promo_text",
        "unit_name"
      ]
    }
  }
}