SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a95ebf734d1602564cb5fe751c2a3bb03d2eccb62f86676d875efbcbff78fc24' 
  AND token = 'mVF0yZ8zLixEps8BIPaQ75fXU3QAeU3ZN1JrQJ7OwUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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