SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9431b4cc53ed02c229aefb413daff148b19321af70053653c5989ab3801d891e' 
  AND token = 'cWnS0pkwW+LAmmWBKhLf2Om70AfvkDIPgkHZChyMp+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}