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, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    182, 41, 56, 57, 30, 112, 246, 89, 197, 
    208, 173, 97, 229, 211, 210, 209, 67, 
    25, 116, 213, 215, 226, 200, 154, 53, 
    52, 111, 82, 84, 228, 85, 88, 26, 35, 47, 
    81, 107, 109, 91, 92, 161, 188, 202, 203, 
    34, 31, 38, 80
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00079

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "115.21"
    },
    "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",
      "index_condition": "((`danishecarter_latest`.`cscart_product_descriptions`.`product_id` in (182,41,56,57,30,112,246,89,197,208,173,97,229,211,210,209,67,25,116,213,215,226,200,154,53,52,111,82,84,228,85,88,26,35,47,81,107,109,91,92,161,188,202,203,34,31,38,80)) and (`danishecarter_latest`.`cscart_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "105.61",
        "eval_cost": "9.60",
        "prefix_cost": "115.21",
        "data_read_per_join": "219K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "unit_name"
      ]
    }
  }
}