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Johnston" Date: Sun, 3 May 2026 12:02:49 -0700 X-Gm-Features: AVHnY4KJIOU7IkN73PzYeKpk_v1mKIqI5VpCZWRHFxiZsuSaBhMHOFHboVsfzu0 Message-ID: Subject: Re: Trying to understand Tuple Header To: "Subramanian,Ramachandran" Cc: "pgsql-novice@lists.postgresql.org" Content-Type: multipart/alternative; boundary="000000000000e67e9c0650ee7524" List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --000000000000e67e9c0650ee7524 Content-Type: text/plain; charset="UTF-8" On Sunday, May 3, 2026, Subramanian,Ramachandran < ramachandran.subramanian@alte-leipziger.de> wrote: > How does postgres know that this 4th tuple has been rolled back ? Please > help me learn that. > > The pg_xact file holds information pertaining to whether a transaction produced live or dead tuples upon ending. David J. --000000000000e67e9c0650ee7524 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sunday, May 3, 2026, Subramanian,Ramachandran <ramachandran.subramanian@alte-leipz= iger.de> wrote:

How does postgres know that this 4th tuple has been rolled b= ack ?=C2=A0 Please help me learn that.


The pg_xact file holds in= formation pertaining to whether a transaction produced live or dead tuples = upon ending.

David J.

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