SELECT  [Sales].[Customer].[CustomerID] AS 'Client ID',
		CONCAT([LastName],', ',[FirstName]) AS 'Name' ,
		COUNT(*) AS 'Amount of orders'
FROM [Sales].[Customer]
INNER JOIN [Person].[Person]
	ON ([BusinessEntityID] = [CustomerID])
LEFT JOIN [Sales].[SalesOrderHeader]
	ON [Sales].[SalesOrderHeader].[CustomerID]  = [Sales].[Customer].[CustomerID]
GROUP BY [Sales].[Customer].[CustomerID],
		 [FirstName],
		 [LastName]
HAVING COUNT(*) >= 25
ORDER BY COUNT(*) DESC ;