This is a very open ended question.

you might start here: http://www.sqlservercentral.com/articles/Performance+Tuning+and+Scaling/indexcreationguidelines/1389/

Clustered indexes (only 1 per table) are good for range queries.

Nonclustered are good for seeks to specific rows.

You generally...

What do you mean reduce duplication?

Litespeed (and Red Gage/Hyperbac) perform compression, which involves some tokens and pattern replacement, just like ZIP files.

Litespeed, and the other vendors, provide utilitis to uncompress...

The MDF specification isn't available. This is meant to be read by the SQL Server service only. To extract tables, you'd connect to the SQL Server service and select them...

There are a number of DMVs that can get you server information. You can start here: http://www.codeproject.com/KB/database/Dynamic_Management_Views.aspx

Which new table? Replication is by publication, so if you create a new table, you need a new replication publication.

Usually you'll find if there's a network glitch, the backup will fail. I almost never run the backup across the network. run it locally and copy it.

nope, backup, detach, uninstall, reinstall.

sp_help_revlogin to save logins.

I don't think this is allowed directly. Maybe with a UDF?

I'd think that something must have changed. If not, the DBCC shouldn't have doubled.

One thing to note, that checkdb includes a checkcatalog and checktable. Paul Randal has a series on...

Check the snapshot.sys.users to see what's mapped there and see if you have unmatched SIDs.

Or run sp_change_users_login with the reporting option.

Should work, and there are some new tools from Microsoft to help check for SQL Injection.

http://blogs.msdn.com/sqlsecurity/archive/2008/06/24/microsoft-source-code-analyzer-for-sql-injection-june-2008-ctp.aspx

Short answer, no.

You can check sp_msforeachtable, but that doesn't cover columns.

What do you mean "write the exam"? That doesn't make sense.

either you want to take the exam, meaning register for and answer questions on the test, or you want to...

Is the database in full recovery mode? You could get a log reader from Apex SQL or Lumigent

Red gate, quest, Hyperbac, all have good solutions. Test them all, check out the features and support and see what you think. They all fit slightly different niches.

Disclosure: I work...