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 (
    91516, 85126, 86183, 86206, 86507, 86783, 
    89078, 85319, 85416, 85467, 85518, 
    82636, 82637, 83533, 83534, 82854, 
    82927, 83000, 83516, 83524, 85365, 
    89070, 83613, 82830, 82903, 82976, 
    85066, 85067, 85152, 85153, 85198, 
    85199, 85244, 85245, 89773, 89774, 
    86138, 86139, 86161, 86162, 86646, 
    86647, 86715, 86716, 86149, 86172, 
    86186, 86209, 86510, 86665, 86734, 
    86786, 83056, 83605, 90892, 90971, 
    85106, 85107, 89824, 89876, 89948, 
    91514, 83059, 83608, 90895, 90974, 
    85322, 85419, 85470, 85521, 82635, 
    83532, 85065, 85151, 85197, 85243, 
    82838, 82839, 82911, 82912, 82984, 
    82985, 83398, 83399, 83408, 83409, 
    85368, 86137, 86160, 86645, 86714, 
    82857, 82930, 83003, 83519, 83527
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00165

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "43.24"
    },
    "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",
      "cost_info": {
        "read_cost": "33.64",
        "eval_cost": "9.60",
        "prefix_cost": "43.24",
        "data_read_per_join": "366K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (91516,85126,86183,86206,86507,86783,89078,85319,85416,85467,85518,82636,82637,83533,83534,82854,82927,83000,83516,83524,85365,89070,83613,82830,82903,82976,85066,85067,85152,85153,85198,85199,85244,85245,89773,89774,86138,86139,86161,86162,86646,86647,86715,86716,86149,86172,86186,86209,86510,86665,86734,86786,83056,83605,90892,90971,85106,85107,89824,89876,89948,91514,83059,83608,90895,90974,85322,85419,85470,85521,82635,83532,85065,85151,85197,85243,82838,82839,82911,82912,82984,82985,83398,83399,83408,83409,85368,86137,86160,86645,86714,82857,82930,83003,83519,83527)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}