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 (
    92255, 92256, 92257, 92496, 92497, 92498, 
    92499, 92254, 92512, 92520, 92522, 
    84280, 84285, 84288, 84954, 84048, 
    92515, 92516, 92519, 84278, 84279, 
    84283, 84284, 84287, 92510, 92517, 
    92521, 84956, 92550, 92509, 92511, 
    92518, 84047, 84277, 84282, 92514, 
    92549, 85010, 92542, 92543, 84273, 
    84275, 84955, 84276, 84281, 84286, 
    85011, 92513
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00060

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 (92255,92256,92257,92496,92497,92498,92499,92254,92512,92520,92522,84280,84285,84288,84954,84048,92515,92516,92519,84278,84279,84283,84284,84287,92510,92517,92521,84956,92550,92509,92511,92518,84047,84277,84282,92514,92549,85010,92542,92543,84273,84275,84955,84276,84281,84286,85011,92513)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
84047 nuie Belfast Sink 795 x 460 x 245mm - White
84048 nuie Belfast Sink 895 x 460 x 245mm - White
84273 nuie Butler Sink 795 x 500 x 220mm - White
84275 nuie Butler Sink comes with Overflow 795 x 500 x 220mm - White
84276 nuie Butler Sink comes with Tap Ledge 595 x 450 x 220mm - White
84277 nuie Butler Sink comes with Tap Ledge 795 x 500 x 220mm - White
84278 nuie Butler Sink Flush Weir 795 x 500 x 220mm - White
84279 nuie Butler Sink Stepped Weir 795 x 500 x 220mm - White
84280 nuie Butler Sink Stepped Weir 895 x 550 x 220mm - White
84281 nuie Butler Sink comes with Overflow and Tap Ledge 595 x 450 x 220mm - White
84282 nuie Butler Sink comes with Overflow and Tap Ledge 795 x 500 x 220mm - White
84283 nuie Butler Sink Flush Weir & Overflow 795 x 500 x 220mm - White
84284 nuie Butler Sink Stepped Weir & Overflow 795 x 500 x 220mm - White
84285 nuie Butler Sink Stepped Weir & Overflow 895 x 550 x 220mm - White
84286 nuie Butler Sink comes with Overflow and Tap Ledge 595 x 450 x 220mm - White
84287 nuie Butler Sink Flush Weir & Overflow 795 x 500 x 220mm - White
84288 nuie Butler Sink Stepped Weir & Overflow 895 x 550 x 220mm - White
84954 nuie Fireclay Sinks Fireclay Cleaner Sink with Grid 515mm x 535mm x 393mm - White
84955 nuie Fireclay Sinks Fireclay Cleaner Sink with Grid 455mm x 362mm x 396mm - White
84956 nuie Fireclay Sinks Fireclay Cleaner Sink with Grid 515mm x 382mm x 393mm - White
85010 nuie Counter Top Sink 1.5 Bowl 1010 x 525mm - White
85011 nuie Counter Top Sink Single Bowl 1010 x 525mm - White
92254 BC Designs Bath Wastes Overflow Filler & Push Down Waste - Chrome
92255 BC Designs Bath Wastes Overflow Filler & Push Down Waste - Copper
92256 BC Designs Bath Wastes Overflow Filler & Push Down Waste - Gold
92257 BC Designs Bath Wastes Overflow Filler & Push Down Waste - Nickel
92496 BC Designs Overflow Filler & Push Down Waste - Brushed Chrome
92497 BC Designs Overflow Filler & Push Down Waste - Brushed Copper
92498 BC Designs Overflow Filler & Push Down Waste - Brushed Gold
92499 BC Designs Overflow Filler & Push Down Waste - Brushed Nickel
92509 nuie Belfast Sink 595mm x 455mm x 254mm - Black
92510 nuie Butler Sink Stepped Weir & Overflow 795mm x 500mm x 220mm - White
92511 nuie Butler Sink 595mm x 450mm x 220mm - Black
92512 nuie Butler Sink Full Weir 795mm x 500mm x 220mm - Black
92513 nuie Butler Sink Fluted with Overflow 595mm x 450mm x 220mm - White
92514 nuie Butler Sink Fluted with Overflow 795mm x 500mm x 220mm - White
92515 nuie Butler Sink Fluted Stepped Weir & Overflow 795mm x 500mm x 220mm - White
92516 nuie Butler Sink Fluted Full Weir & Overflow 795mm x 500mm x 220mm - White
92517 nuie Counter Top Sink 1.5 Bowl 1010mm x 525mm - White
92518 nuie Counter Top Sink Single Bowl 1010mm x 525mm - White
92519 nuie Counter Top Sink 1.5 Bowl 1010mm x 525mm - Black
92520 nuie Counter Top Sink 1.5 Bowl 1010mm x 525mm - Black
92521 nuie Counter Top Sink Single Bowl 1010mm x 525mm - Black
92522 nuie Counter Top Sink Single Bowl 1010mm x 525mm - Black
92542 nuie Inset Single Bowl with Overflow 711mm x 483mm x 254mm - White
92543 nuie Inset Single Bowl with Overflow 762mm x 457mm x 254mm - White
92549 nuie Inset Single Bowl with Overflow 548mm x 442mm x 197mm - Black
92550 nuie Inset Round Single Bowl with Overflow & Central Waste 460mm x 191mm - Black