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 (
    86915, 86916, 86917, 86918, 86919, 86974, 
    86975, 86976, 86977, 86978, 86979, 
    86980, 87035, 87036, 87037, 87038, 
    87039, 87040, 87041, 87093, 87094, 
    87095, 87096, 87097, 87098, 87099, 
    84638, 84639, 84636, 84637, 91014, 
    91026, 91038, 91051, 84506, 84507, 
    84572, 84573, 84661, 84662, 89057, 
    84504, 84505, 84570, 84571, 89059, 
    89060, 84634
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00122

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.62"
    },
    "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": "16.82",
        "eval_cost": "4.80",
        "prefix_cost": "21.62",
        "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 (86915,86916,86917,86918,86919,86974,86975,86976,86977,86978,86979,86980,87035,87036,87037,87038,87039,87040,87041,87093,87094,87095,87096,87097,87098,87099,84638,84639,84636,84637,91014,91026,91038,91051,84506,84507,84572,84573,84661,84662,89057,84504,84505,84570,84571,89059,89060,84634)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
84504 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Left Hand Combination 1500mm - Anthracite Woodgrain
84505 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Right Hand Combination 1500mm - Anthracite Woodgrain
84506 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Left Hand Combination 1500mm - Anthracite Woodgrain
84507 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Right Hand Combination 1500mm - Anthracite Woodgrain
84570 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Left Hand Combination 1500mm - Hacienda Black
84571 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Right Hand Combination 1500mm - Hacienda Black
84572 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Left Hand Combination 1500mm - Hacienda Black
84573 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Right Hand Combination 1500mm - Hacienda Black
84634 Hudson Reed Fusion Floor Standing 4 Door Vanity Basin Left Hand Combination 1200mm - Gloss Grey
84636 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Left Hand Combination 1500mm - Gloss Grey
84637 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Right Hand Combination 1500mm - Gloss Grey
84638 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Left Hand Combination 1500mm - Gloss Grey
84639 Hudson Reed Fusion Floor Standing 3 Door Vanity Basin & WC Right Hand Combination 1500mm - Gloss Grey
84661 Hudson Reed Fusion Wall Hung 4 Drawer Vanity Unit & Twin Polymarble Basin 1200mm - Gloss Grey
84662 Hudson Reed Fusion Wall Hung 4 Drawer Vanity Unit & Twin Ceramic Basin 1200mm - Gloss Grey
86915 Old London Old London Storm Grey Floor Standing 2 Door Vanity Basin Unit with Square Basin & 1 Tap Hole Marble Top, 600mm - Storm Grey
86916 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole Grey Marble Top 600mm - Storm Grey
86917 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole Black Marble Top 600mm - Storm Grey
86918 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole White Marble Top 600mm - Storm Grey
86919 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole Grey Marble Top 600mm - Storm Grey
86974 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole Black Marble Top 600mm - Twilight Blue
86975 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole White Marble Top 600mm - Twilight Blue
86976 Old London Old London Twilight Blue Floor Standing 2 Door Vanity Basin Unit with Square Basin & 1 Tap Hole Marble Top, 600mm - Twilight Blue
86977 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole Grey Marble Top 600mm - Twilight Blue
86978 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole Black Marble Top 600mm - Twilight Blue
86979 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole White Marble Top 600mm - Twilight Blue
86980 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole Grey Marble Top 600mm - Twilight Blue
87035 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole Black Marble Top 600mm - Timeless Sand
87036 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole White Marble Top 600mm - Timeless Sand
87037 Old London Old London Timeless Sand Floor Standing 2 Door Vanity Basin Unit with Square Basin & 1 Tap Hole Marble Top, 600mm - Timeless Sand
87038 Old London Floor Standing 2 Door Vanity Unit with 1 Tap Hole Grey Marble Top 600mm - Timeless Sand
87039 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole Black Marble Top 600mm - Timeless Sand
87040 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole White Marble Top 600mm - Timeless Sand
87041 Old London Floor Standing 2 Door Vanity Unit with 3 Tap Hole Grey Marble Top 600mm - Timeless Sand
87093 Old London Floor Standing 3 Door Vanity Unit with 1 Tap Hole Black Marble Top 600mm - Hunter Green
87094 Old London Floor Standing 3 Door Vanity Unit with 1 Tap Hole White Marble Top 600mm - Hunter Green
87095 Old London Old London Hunter Green Floor Standing 4 Door Vanity Basin Unit with Square Basin & 1 Tap Hole Marble Top, 1200mm - Hunter Green
87096 Old London Floor Standing 3 Door Vanity Unit with 1 Tap Hole Grey Marble Top 600mm - Hunter Green
87097 Old London Floor Standing 3 Door Vanity Unit with 3 Tap Hole Black Marble Top 600mm - Hunter Green
87098 Old London Floor Standing 3 Door Vanity Unit with 3 Tap Hole White Marble Top 600mm - Hunter Green
87099 Old London Floor Standing 3 Door Vanity Unit with 3 Tap Hole Grey Marble Top 600mm - Hunter Green
89057 Hudson Reed Quartet Wall Hung 4 Drawer Double Cabinet with Twin Polymarble Basin 1440mm - Gloss Grey
89059 Hudson Reed Quartet Wall Hung 4 Drawer Double Cabinet with Sparkling Black Worktop 1440mm - Gloss Grey
89060 Hudson Reed Quartet Wall Hung 4 Drawer Double Cabinet with Sparkling White Worktop 1440mm - Gloss Grey
91014 Hudson Reed Bexley Floor Standing 2 Door 1 Shelf Vanity & Single Bowl 1 Tap Hole Marble Top, 800mm - Satin White/White
91026 Hudson Reed Bexley Floor Standing 2 Door 1 Shelf Vanity & Single Bowl 1 Tap Hole Marble Top, 800mm - Cool Grey/White
91038 Hudson Reed Bexley Floor Standing 2 Door 1 Shelf Vanity & Single Bowl 1 Tap Hole Marble Top, 800mm - Indigo Blue/White
91051 Hudson Reed Bexley Floor Standing 2 Door 1 Shelf Vanity & Single Bowl 1 Tap Hole Marble Top, 800mm - Matt Green/White