Posted by Erland Sommarskog on 06/08/05 01:15

Ellen K (ekaye2002@yahoo.com) writes:
> It was my understanding (Please correct me if I'm wrong on this!) that
> BLOB data actually reside on their own separate pages and a BLOB field
> only holds a pointer to the location of the actual data, therefore the
> BLOB data per se would not get written to the log, only the pointer
> would be written.

A BLOB normally resides on its own page. However, this page is also
logged, else ROLLBACK TRANSACTION would be very tragic.

> If log shipping works by applying the transaction log to the standby
> database, then what happens to the BLOB data?

It's shipped as well.

> Related question, how does transactional replication work? Is it also
> based on the transaction log?

Yes. I don't remember the exact details, but basically log entries are
sent to the distributor which spreads them around. Note an important
feature of transacional replication is that what is a transaction in
the publisher, is also a transaction in the subscribers.

--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techinfo/productdoc/2000/books.asp

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