Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8638f00e7be022b2e17679b72810f75a3378ab83b8d46e524ef78cde0ddd3e2' 
  AND token = 'kLrKSXxsFuNSAQtDqu+0Nz8IpJmRSOfu4PgWbbnyObs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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