| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Vignesh Raghunathan <vignesh(dot)pgsql(at)gmail(dot)com> |
| Cc: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Size of TOAST pointer |
| Date: | 2015-07-16 22:49:58 |
| Message-ID: | 13171.1437086998@sss.pgh.pa.us |
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| Lists: | pgsql-hackers |
Vignesh Raghunathan <vignesh(dot)pgsql(at)gmail(dot)com> writes:
> I was looking at the documentation for TOAST (
> http://www.postgresql.org/docs/devel/static/storage-toast.html) and it's
> specified that the toast pointer occupies 18 bytes. However, the struct
> representing the toast pointer is defined as follows
> typedef struct varatt_external
The data that actually ends up on disk is a varattrib_1b_e wrapping a
varatt_external, and that header is where the extra 2 bytes come from.
regards, tom lane
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