SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2919c1523ffa4e2cad8e9cb4f471bb128e88473fa37cdfdba1ecc3e31eb24e3d' 
  AND token = 'EVGfITjR8MwYgLmGEEOqGEjn6DLGbolrYQt6FVmTlu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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