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 (
    3351, 78822, 3316, 3317, 2512, 3326, 
    3327, 3374, 3331, 3335, 3377, 3376, 
    3313, 3368, 3311, 3315, 3314, 3310, 
    3312, 3330, 3332, 3333, 3334, 3336, 
    3337, 3338, 3339, 3340, 3341, 3342, 
    3343, 3344, 3345, 3346, 3347, 3318, 
    3319, 3320, 3322, 3321, 3328, 3324, 
    3323, 3329, 3354, 3378, 3379, 3355, 
    3369, 3371, 3356, 3357, 3358, 3359, 
    3360, 3361, 3362, 3363, 3364, 3365, 
    3366, 3367, 3373, 3375
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00137

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.11207368,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_descriptions",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "product_id"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["product_id", "lang_code"],
          "loops": 1,
          "rows": 64,
          "cost": 0.11207368,
          "filtered": 100,
          "attached_condition": "cscart_product_descriptions.product_id in (3351,78822,3316,3317,2512,3326,3327,3374,3331,3335,3377,3376,3313,3368,3311,3315,3314,3310,3312,3330,3332,3333,3334,3336,3337,3338,3339,3340,3341,3342,3343,3344,3345,3346,3347,3318,3319,3320,3322,3321,3328,3324,3323,3329,3354,3378,3379,3355,3369,3371,3356,3357,3358,3359,3360,3361,3362,3363,3364,3365,3366,3367,3373,3375) and cscart_product_descriptions.lang_code = 'en'"
        }
      }
    ]
  }
}