Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4353fbe1ff80ed4ceba5c00d7f0a6701ff36c14db921b6ad2a0ab3821bcfeb86' 
  AND token = 'cLuhhoX2+56IO6qBKsDmEJn8ORKi5a2K5yWAnXGGVCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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