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From: Tom Lane <tgl@sss.pgh.pa.us>
To: benj.dev@laposte.net
cc: pgsql-docs@lists.postgresql.org
Subject: Re: HeapTupleHeaderData Layout description
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Comments: In-reply-to benj.dev@laposte.net
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benj.dev@laposte.net writes:
> In https://www.postgresql.org/docs/13/storage-page-layout.html<br>
> we can find on =C2=A7 68.6.1. Table Row Layout<br>
> the Table 68.4. HeapTupleHeaderData Layout<br>
> <br>
> When additionning Length of differents Fields taht are present we obtain=
&nbsp; atotal of<br>
> 4+4+4+4+6+2+2+1 =3D 27<br>

I think you missed the point that t_cid overlays with t_xvac.

			regards, tom lane