SELECT p.*, x.*
FROM Projects p
CROSS APPLY (
	SELECT TOP 1 *
	FROM ProjectCategory pc
	WHERE pc.ProjectID = p.ProjectID
	ORDER BY NEWID()
) x

/*
SELECT p.*, x.*
FROM ProjectCategory pc
CROSS APPLY (
	SELECT TOP 1 *
	FROM Project p
	WHERE pc.ProjectID = p.ProjectID
	ORDER BY NEWID() -- p.ProjectID
) x
*/
use AdventureWorks2008
go
set statistics io on
go
--"any of", for example ordered by ProductID
SELECT 
	CategoryName = x.Name,
	SampleProductName = pc.Name	
FROM Production.ProductSubcategory pc
CROSS APPLY (
	SELECT TOP 1 *
	FROM Production.Product p
	WHERE pc.ProductSubcategoryID = p.ProductSubcategoryID
	ORDER BY  p.ProductID
) x
/*
Table 'Product'. Scan count 1, logical reads 395, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'ProductSubcategory'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
*/
go

-- pseudo random
SELECT 
	CategoryName = x.Name,
	SampleProductName = pc.Name	
FROM Production.ProductSubcategory pc
CROSS APPLY (
	SELECT TOP 1 *
	FROM Production.Product p
	WHERE pc.ProductSubcategoryID = p.ProductSubcategoryID
	ORDER BY  newid()
) x
/*
Table 'Product'. Scan count 37, logical reads 555, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'ProductSubcategory'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

*/
go
set statistics io off