SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c99266bb9d30b186079ff5992f16c4a724d1a426ad48a288c65f2e98e174368' 
  AND token = 'cvH3a12DRsUsl/aaAcsZBhb65r/ZBFWC15qKHpj4IGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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