SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ebd1aaf278cdb910566dae148656f281b3b1bb85b1124948b250c3a4baedb9b' 
  AND token = 'O9Uc+giTOpBRpZsc8pz3HlRTK6lJKdfSSN4uTF0Cb4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}