Log shipping data

For log shipping, is all of the data entered into the primary shipped
via the transaction log to the secondary? I guess it is more of a
transaction log question. Does the transaction log also contain all
of the data stored in the db tables? If yes, does this mean there is
duplication of data - storage of the same data in the mdf and ldf
files?The transaction log keeps all changes to application / system data in the
database are recorded serially in the transaction log. Using this
information, the DBMS can track which transaction made which changes to SQL
Server data.
Information recorded on the transaction log includes:-
1. beginning of each transaction
2. Actual changes made to the data and info to undo the modifications made
during each transaction
3. Allocation changes and deallocation changes of database pages
Using this data, Microsoft SQL Server can accomplish data integrity
operations to ensure consistent data is maintained in the database. The
transaction log is used when SQL Server is restarted, when transactions are
rolled back, and to restore the database to the state prior to the
transaction.
So transaction log is not duplicated. Once the transaction is writtent to
disk automatically it will clear the LDF file
for SIMPLE recovery model and for FULL and BULK_LOGGED the LDF file will be
cleared after the trasbnaction log backup.
Which will help while there is a recovery/poin_in_time recovery needed.
THis is a very broad topic. please go thru transaction log and Recovery
model topics in books online.
Thanks
Hari
"erdos" <account@.cygen.com> wrote in message
news:1176439295.175918.296680@.w1g2000hsg.googlegroups.com...
> For log shipping, is all of the data entered into the primary shipped
> via the transaction log to the secondary? I guess it is more of a
> transaction log question. Does the transaction log also contain all
> of the data stored in the db tables? If yes, does this mean there is
> duplication of data - storage of the same data in the mdf and ldf
> files?
>