Thread: Description of transaction model for indexes

Description of transaction model for indexes

From
Gerhard Wiesinger
Date:
Hello!

The transaction model is discussed in several areas:
http://www.packtpub.com/article/transaction-model-of-postgresql
The POSTGRES Data Model (1987)
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.8578
The Design of POSTGRES (1986)
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.1422

However: Is there a paper available, how indexes are handled inside the
transaction (e.g. visibility (not handled), concurrency, etc.)?
E.g. What happens on SELECT/INSERT/UPDATE/DELETE?

Some aspects can be found in:
http://www.pgcon.org/2008/schedule/attachments/54_PGCon2008-HOT.ppt

Thnx.

Ciao,
Gerhard

--
http://www.wiesinger.com/


Re: Description of transaction model for indexes

From
Erik Jones
Date:
On Jan 4, 2009, at 3:09 AM, Gerhard Wiesinger wrote:

> Hello!
>
> The transaction model is discussed in several areas:
> http://www.packtpub.com/article/transaction-model-of-postgresql
> The POSTGRES Data Model (1987)
> http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.8578
> The Design of POSTGRES (1986)
> http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.1422
>
> However: Is there a paper available, how indexes are handled inside
> the transaction (e.g. visibility (not handled), concurrency, etc.)?
> E.g. What happens on SELECT/INSERT/UPDATE/DELETE?
>
> Some aspects can be found in:
> http://www.pgcon.org/2008/schedule/attachments/54_PGCon2008-HOT.ppt

I don't know about a paper anywhere but index tuples contain pointers
to the data tuples that are followed to determine transactional
visibility.  All HOT does for this is means there may be more than one
pointer to follow in the event of a HOT updated tuple.

Erik Jones, Database Administrator
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