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 (
    86262, 86280, 86867, 86261, 86271, 86281, 
    86283, 86272, 86282, 86277, 86310, 
    87753, 86276, 86353, 86865, 87742, 
    87752, 86275, 86274, 87741, 86242, 
    86240, 87739, 87740, 86239, 86241, 
    87737, 87738, 93401, 93402, 93403, 
    93404, 93405, 93406, 94678, 94679, 
    94680, 94681, 94682, 94683, 94684, 
    94685, 95101, 95102, 95103, 95104, 
    95105, 95106
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00093

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 (86262,86280,86867,86261,86271,86281,86283,86272,86282,86277,86310,87753,86276,86353,86865,87742,87752,86275,86274,87741,86242,86240,87739,87740,86239,86241,87737,87738,93401,93402,93403,93404,93405,93406,94678,94679,94680,94681,94682,94683,94684,94685,95101,95102,95103,95104,95105,95106)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
86239 nuie Straight Ladder Rail 500 x 700mm - Chrome
86240 nuie Straight Ladder Rail 1100 x 500mm - Chrome
86241 nuie Curved Ladder Rail 500 x 700mm - Chrome
86242 nuie Curved Ladder Rail 1100 x 500mm - Chrome
86261 nuie Flat Panel Heated Towel Rail 1213 x 500mm - Chrome
86262 nuie Elgin Heated Towel Rail 1080 x 550mm - Chrome
86271 Hudson Reed Heated Towel Rails Countess 1550 x 600mm - Chrome
86272 Hudson Reed Heated Towel Rails Countess 1550 x 600mm - Chrome
86274 nuie Eton Heated Towel Rail 1200 x 450mm - Chrome
86275 nuie Eton Heated Towel Rail 1200 x 600mm - Chrome
86276 nuie Piazza Heated Towel Rail 950 x 500mm - Chrome
86277 nuie Piazza Heated Towel Rail 1200 x 500mm - Chrome
86280 nuie Piazza Square Flat Towel Radiator 1213mm x 500mm - Brushed Brass
86281 nuie Piazza Square Towel Radiator with Flat Panels 840mm x 500mm - Brushed Brass
86282 nuie Flat Panel Heated Towel Rail 1213 x 500mm - Anthracite
86283 nuie Elgin Heated Towel Rail 1080 x 550mm - Anthracite
86310 nuie Piazza Square Flat Towel Radiator 840mm x 500mm - Anthracite
86353 Hudson Reed Heated Towel Rails Countess 966 x 676mm - Chrome
86865 Hudson Reed Heated Towel Rails Epsom 1500 x 575mm - Chrome
86867 Hudson Reed Heated Towel Rails Adelaide 780 x 685mm - Chrome
87737 nuie Curved Ladder Rail 700 x 500mm - Anthracite
87738 nuie Straight Ladder Rail 700 x 500mm - Anthracite
87739 nuie Curved Ladder Rail 1150 x 500mm - Anthracite
87740 nuie Straight Ladder Rail 1150 x 500mm - Anthracite
87741 nuie Square Ladder Rail 800 x 500mm - Chrome
87742 nuie Square Ladder Rail 1200 x 500mm - Chrome
87752 nuie Lorica Straight Towel Radiator with Round Rails 800mm x 500mm - Brushed Brass
87753 nuie Lorica Straight Towel Radiator with Round Rails 1200mm x 500mm - Brushed Brass
93401
93402
93403
93404
93405
93406
94678
94679
94680
94681
94682
94683
94684
94685
95101
95102
95103
95104
95105
95106