To recover the database

 

1.

Make a copy of the database and log file.

 

2.

Restore the database (.db ) file, not the log file, from tape into a

 

 

temporary directory.

 

3.

In the temporary directory, start the database, applying the old logs using

 

 

the -aoption, applying the named transaction logs in the correct order.

 

4.

Start the database using the current transaction log and the -aoption, to

 

 

apply the transactions and bring the database file up to date.

 

5.

Start the database in your normal way. Any new activity will be appended

 

 

to the current transaction log.

Example

Suppose you have a consolidated database file named c:\dbdir\cons.db. The

 

transaction log file c:\dbdir\cons.log is mirrored to d:\mirdir\cons.mlg.

 

Assume that you perform full backups weekly, and you perform incremental

 

backups daily using the following command:

 

 

dbbackup -c "uid=DBA;pwd=SQL" -r -t E:nBACKDIR

 

This command backs up the transaction log cons.log to the directory

 

e:\backdir. The transaction log file is then renamed to datexx.log, where date

 

is the current date and xx is the next set of letters in sequence, and a new

 

transaction log is started. The directory e:\backdir is then backed up using a

 

third-party utility.

 

In this scenario you would be running the Message Agent with the optional

 

directory to point to the renamed transaction log files. The Message Agent

 

command line would be

 

 

dbremote -c "uid=DBA;pwd=SQL" C:nDBDIR

 

On the third day following the weekly backup the database file gets

 

corrupted because of a bad disk block.

 

To recover from media failure on the C drive

 

1.

Backup the mirrored transaction log d:\mirdir\cons.mlg.

 

2.

Create a temporary directory to perform the recovery in. We will call it

 

 

c:\recover.

 

3.

Restore the most recent backup of the database file, cons.db to

 

 

c:\recover\cons.db.

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Sybase DC38133-01-0902-01 Make a copy of the database and log file, Temporary directory, To the current transaction log