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 (
    84651, 84585, 84631, 84621, 84677, 84321, 
    84499, 84565, 84489, 84555, 84545, 
    84611, 84301, 84291, 84667, 84347, 
    84535, 84601, 84546, 84612, 84348, 
    101134, 101135, 101136, 101137, 101138, 
    101139, 101140, 101141, 101142, 101143, 
    101144, 101145, 101146, 101147, 101148, 
    101149, 101150, 101151, 101152, 101153, 
    101154, 101155, 101156, 101157, 101158, 
    101159, 101160, 101161, 101162, 101163, 
    101164, 101165, 101166, 101167, 101168, 
    101169, 101170, 101171, 101172, 101173, 
    101174, 101175, 101176, 101177, 101178, 
    101179, 101180, 101181, 101182, 101183, 
    101184, 101185, 101186, 101187, 101188, 
    101189, 101190, 101191, 101192, 101193, 
    101194, 101195, 101196, 101197, 101198, 
    101199, 101200, 101201, 101202, 101203, 
    101204, 101205, 101206, 101207, 101208
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00079

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 (84651,84585,84631,84621,84677,84321,84499,84565,84489,84555,84545,84611,84301,84291,84667,84347,84535,84601,84546,84612,84348,101134,101135,101136,101137,101138,101139,101140,101141,101142,101143,101144,101145,101146,101147,101148,101149,101150,101151,101152,101153,101154,101155,101156,101157,101158,101159,101160,101161,101162,101163,101164,101165,101166,101167,101168,101169,101170,101171,101172,101173,101174,101175,101176,101177,101178,101179,101180,101181,101182,101183,101184,101185,101186,101187,101188,101189,101190,101191,101192,101193,101194,101195,101196,101197,101198,101199,101200,101201,101202,101203,101204,101205,101206,101207,101208)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}