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Re: libpq: empty arrays have rank 0 in binary results? whatever the type's rank? - Mailing list pgsql-general

From Dominique Devienne
Subject Re: libpq: empty arrays have rank 0 in binary results? whatever the type's rank?
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Msg-id CAFCRh-_N066y3r5EE6tzdrsd=eQOU=xEBnr_eUMu=oBfzHDJbQ@mail.gmail.com
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In response to Re: libpq: empty arrays have rank 0 in binary results? whatever the type's rank?  (Tom Lane <tgl@sss.pgh.pa.us>)
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On Wed, Mar 29, 2023 at 3:45 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
Dominique Devienne <ddevienne@gmail.com> writes:
> Hi. Selecting/fetching an empty 1D array using a binary-mode PGresult,
> gives me back 12 bytes, and the first 4, the rank, is 0, something I was
> not expecting.

Yeah, empty arrays have zero dimensions.

> PS: On a side note; where can I find the sending code for arrays?
> I didn't find the usual _send() and _recv() functions (but looking on
> github online...)

https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/adt/arrayfuncs.c;h=87c987fb2704761c59333bf8c1fee47e5c14c598;hb=HEAD#l1583

Great. Thanks Tom. --DD

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