Re: TOAST pointer size

PG Doc comments form <noreply@postgresql.org> writes:
> It would be nice to add a break-down of why the TOAST Pointer size is 18
> bytes

Use the source, Luke.  The useful pointer data is indeed 16 bytes:


https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/include/postgres.h;h=c48f47e930ad05d3ae2e24b0c0c85662cd058a7b;hb=HEAD#l67

but there's varlena tag overhead:


https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/include/postgres.h;h=c48f47e930ad05d3ae2e24b0c0c85662cd058a7b;hb=HEAD#l159

This doesn't seem like appropriate detail for the user docs.

            regards, tom lane