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 (
    100704, 100705, 100706, 100707, 100708, 
    100709, 100710, 100711, 100712, 100713, 
    100714, 100715, 100716, 100717, 100718, 
    100719, 100720, 100721, 100722, 100723, 
    100724, 100725, 100726, 100727, 100728, 
    100729, 100730, 100731, 100732, 100733, 
    100734, 100735, 100736, 100737, 100738, 
    100739, 100740, 100741, 100742, 100743, 
    100744, 100745, 100746, 100747, 100748, 
    100749, 100750, 100751, 100752, 100753, 
    100754, 100755, 100756, 100757, 100758, 
    100759, 100760, 100761, 100762, 100763, 
    100764, 100765, 100766, 100767, 100768, 
    100769, 100770, 100771, 100772, 100773, 
    100774, 100775, 100776, 100777, 100778, 
    100779, 100780, 100781, 100782, 100783, 
    100784, 100785, 100786, 100787, 100788, 
    100789, 100790, 100791, 100792, 100793, 
    100794, 100795, 100796, 100797, 100798, 
    100799
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00146

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 (100704,100705,100706,100707,100708,100709,100710,100711,100712,100713,100714,100715,100716,100717,100718,100719,100720,100721,100722,100723,100724,100725,100726,100727,100728,100729,100730,100731,100732,100733,100734,100735,100736,100737,100738,100739,100740,100741,100742,100743,100744,100745,100746,100747,100748,100749,100750,100751,100752,100753,100754,100755,100756,100757,100758,100759,100760,100761,100762,100763,100764,100765,100766,100767,100768,100769,100770,100771,100772,100773,100774,100775,100776,100777,100778,100779,100780,100781,100782,100783,100784,100785,100786,100787,100788,100789,100790,100791,100792,100793,100794,100795,100796,100797,100798,100799)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}