Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5df6596819464f20bd3ee6a7d6cfc2a7c492aa350843cde7d5ce06f07f9e9dbf' 
  AND token = 'BnJQrZFc9OmqJZ1QSuKmCeG2a5sLhF4VJBHIfG4eyC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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