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 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    92691, 92692, 92693, 92694, 92695, 92696, 
    92697, 92698, 92699, 92700, 92701, 
    92702, 92703, 92704, 92705, 92706, 
    92707, 92708, 92709, 92710, 92711, 
    92712, 92713, 92714, 92715, 92716, 
    92717, 92718, 92719, 92720, 92721, 
    92722, 92723, 92724, 92725, 92726, 
    92727, 92728, 92729, 92730, 92731, 
    92732, 92733, 92734, 92735, 92736, 
    92737, 92738
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00098

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.63"
    },
    "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": 48,
      "rows_produced_per_join": 48,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "16.83",
        "eval_cost": "4.80",
        "prefix_cost": "21.63",
        "data_read_per_join": "183K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (92691,92692,92693,92694,92695,92696,92697,92698,92699,92700,92701,92702,92703,92704,92705,92706,92707,92708,92709,92710,92711,92712,92713,92714,92715,92716,92717,92718,92719,92720,92721,92722,92723,92724,92725,92726,92727,92728,92729,92730,92731,92732,92733,92734,92735,92736,92737,92738)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}