SQL Server Books Online is an absolutely huge resource. With over 58,000 pages that change several times a year, it's like getting all of the books at one time that you are ever going to use from Grade-School through College. Not only that, it is used by beginners, intermediates and experts; by developers, DBAs and architects, and is used as the definitive resource for design experts.
As you can imagine, coming up with a single table of contents that all of these audiences and levels of readers can actually use is somewhat of a daunting task. Over the various releases you've seen the table of contents change, and in the future it will change again as the information grows and changes.
But navigating a table of contents is only one way of finding information. These days most of us have left the traditional "Book" paradigm, since we deal with a huge amount of information that changes rapidly. We're more comfortable with designing a search criteria for data rather than scanning a table of contents to locate it.
Books Online (the connected client, not the web version) has a built-in search mechanism. There's both a button and a tab within the "DExplorer" help tool that is the current delivery mechanism for SQL Server 2005 Books Online which we share with the Visual Studio product. But some readers that use the search tool have found it, well, less than effective. For instance, a typical DBA might want to know the effects of memory settings on Analysis Services, so they enter a search criteria of "memory" in the search bar. However, the first few returns they get deal with loads of memory settings that deal with everything in SQL Server, from the Engine settings out. Not exactly what they needed.
There is a fix to the problem, however. Because Books Online has so much data, you need to filter the results you're looking for. Just below the Search Criteria box are two filters: Technology and Content Type. Changing the Technology filter to show only those topics dealing with Analysis Services returns a much more satisfying top two topics of configuring memory and working with memory in Analysis Services.
To be sure, there are further enhancements that would be useful in this area. But look for this feature to help you narrow down the amazing depth of Information SQL Server Books Online has.
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