SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75585541cce77cbf76002d30d9aa8c7981a11abcfec9de19617bcb37409acce2' 
  AND token = 'mhH19IKM3ScJZRHOeAKKsfEi8aesehvqF9RcOllSOUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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