SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01584db3ab50eb7eb271e10289ab4f5d27cf4b6ebd2b4eaba3da929049230834' 
  AND token = 'pSYZTExUSB9TOkaFR6kXdibsO+DosTZKNFIZu0VIakI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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