Chapter 5. Logging and Recovery

In this chapter:
Transaction Log Basics	149
Changes in Log Size	154
Reading the Log	162
Backing Up and Restoring a Database	162
Summary	174

In the previous chapter, I told you about the data files that are created to hold information in a Microsoft SQL Server database. Every database also has at least one file that stores its transaction log. I made reference to SQL Server transaction logs and log files in Chapter 4, but I did not really go into detail about how a log file is different from a data file and exactly how SQL Server uses its log files. In this chapter, I'll tell you about the structure of SQL Server log files and how they're managed when transaction information is logged. I'll explain how SQL Server log files grow and when and how a log file can be reduced in size. Finally, we'll look at how log files are used during SQL Server backup and restore operations and how they are affected by your database's recovery model.