If your looking for a quick and easy way to get a fast query, sure, go with a flat table design. However, that doesn't exactly fit in to a *relational* database. For that much you could simply store your data in a text or xml file on the file system.

Instead of asking a generic question without any info, provide some details so we can help you the correct way. Post your table structures, query and execution plan and then we can help.

Mark