SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '857b9cc284c81b2495c76c33b418326e7a522c9095fe0fd870e92800ce1b3010' 
  AND token = 'ia8rydU33jil7aG6UhNzyiNlLtMP7SRwA4QRFoWU+h4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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