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Re: Way to access LSN (for each transaction) by directly talking to postgres? - Mailing list pgsql-hackers

From Joshua Bay
Subject Re: Way to access LSN (for each transaction) by directly talking to postgres?
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Msg-id CABb-U3axvtZKEKr1VT-CTDwFton8jLPEQvydWN4vL-ZODp4g8w@mail.gmail.com
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In response to Re: Way to access LSN (for each transaction) by directly talking to postgres?  (Craig Ringer <craig@2ndquadrant.com>)
Responses Re: Way to access LSN (for each transaction) by directly talking to postgres?  (Craig Ringer <craig@2ndquadrant.com>)
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Thanks for responses!

The problem I wanted to solve was to find the (global) order of commits across the postgres cluster. So, my attempt was to use the LSN.



On Wed, Aug 3, 2016 at 9:47 AM, Craig Ringer <craig@2ndquadrant.com> wrote:


On 3 August 2016 at 11:37, Joshua Bay <joshuabay93@gmail.com> wrote:
Hi,

Could you please let me know if there is a way to get LSN of each transaction by directly communicating with Postgres server and NOT by accessing logs.


To what end? What problem are you trying to solve?

What LSN, exactly? The LSN of the first write and xid allocation? The LSN of the commit record? What if it's a complex commit like with prepared xacts?


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 Craig Ringer                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

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