SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a25dd981dbbe4f85aa52b8674f198d9289657355e5dc0841459165a0d6a62bf' 
  AND token = 'FwXeHPW/gafx+qyUtFbacc8Z+1iheiqFbkrOGmQjG78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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