Why Back Up?

Today's hardware and software components are many times more reliable than those of the not-so-distant past; however, they will never be perfect, and there is always the chance of having some type of failure. It is therefore prudent to always have some type of "safety net" in place at all times, so that if a situation arises that results in the loss or damage of online data, production can be restored quickly with minimal or no loss of data. When people think of situations that could result in the loss of data, they typically think of disk crashes. There are, however, other situations that can have the same end result but are not as often considered when planning for recovery. Some of these problems include:

• Disk subsystem failure
• Systems software failure
• Accidental or malicious use of deletion statements (for example, delete from prod_table, drop database customers, format c:, and so on)
• Accidental or malicious use of updating statements (for example, expecting to update one row in a table but not qualifying the WHERE clause, so all rows are updated)
• Destructive viruses
• Natural disasters (fire, flood, earthquake, and so on)
• Theft

As the remainder of this appendix will show, Microsoft SQL Server provides many fast and reliable ways to back up your data. To ensure that your data is safeguarded, you need to define a solid backup strategy.