hello,  what are these statistical guides based on data guides in monetdb. And did monetdb stores these statistical guides(data guides). And if yes where it stores it & how can we access it . & does the physical algebra plan depend only on these statistical guides at compile time without actually running the query. And what are children Histogram & Typed valued Histogram , & are these Histograms are stored & if yes how can we access it. Your Mail works best with the New Yahoo Optimized IE8. Get it NOW!. The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. http://in.yahoo.com/