Where can I find documentation on SQL Server internals?

Question

I know, well I've been told, Microsoft has a per-dev doc system under MSDN. Specifically, I'm looking for docs on the internal format of the WAL log. Is this documented anywhere? Certainly third parties must have access to this?

And, moreover, is there anyway to know what exactly is documented with MSDN without first paying for it?

What other source of documentation is there on the SQL Server internals?

• McNets: You can get some info here: solutioncenter.apexsql.com/read-a-sql-server-transaction-log

Answer 1

I'm looking for docs on the internal format of the WAL log

The SQL Server Log File is not publicly documented, but there is a partner program for 3rd parties that want to build solutions that use it directly. EG Attunity, Quest, etc.

And, moreover, is there anyway to know what exactly is documented with MSDN without first paying for it?

There is ZERO additional documentation available to MSDN subscribers. All published documentation and support material is published to the web.

The best sources for SQL Server Internals are the work of Kalen Delaney https://www.red-gate.com/simple-talk/author/kalen-delaney/ and Paul Randal https://www.sqlskills.com/blogs/paul/.

In particular Paul has some posts on reading the SQL Log. eg https://www.sqlskills.com/blogs/paul/using-fn_dblog-fn_dump_dblog-and-restoring-with-stopbeforemark-to-an-lsn/

Answer 2

What other source of documentation is there on the SQL Server internals?

Aside from what David already answered, I believe these are the most comprehensive guide to SQL Server Transaction Log Internals and Understanding How SQL Server Executes A Query that are free from the web. A must read blog.

Thanks to Remus!