Re: Large expressions in indexes can't be stored (non-TOASTable)

On Wed, Apr 9, 2025, at 4:05 PM, Nathan Bossart wrote:
> On Wed, Apr 09, 2025 at 01:20:29PM +0900, Michael Paquier wrote:
> > I guess that's the consensus, then. No objections to the removal here.
>
> That would look like the attached. There are still a couple of other known
> TOAST snapshot issues I need to revisit, but this sidesteps a few of them.
> But this'll need to wait for a couple of months until v19 development
> begins.

LGTM. I have a few suggestions.

+ /*
+ * To avoid needing a TOAST table for pg_replication_origin, we restrict
+ * replication origin names to 512 bytes. This should be more than enough
+ * for all practical use.
+ */
+ if (strlen(roname) > MAX_RONAME_LEN)
+ ereport(ERROR,

I wouldn't duplicate the comment. Instead, I would keep it only in origin.h.

+ errdetail("Repilcation origin names must be no longer than %d bytes.",
+ MAX_RONAME_LEN)));

s/Repilcation/Replication/

+#define MAX_RONAME_LEN (512)

It is just a cosmetic suggestion but I usually use parentheses when it is an
expression but don't include it for a single number.

Should we document this maximum length?

--
Euler Taveira
EDB https://www.enterprisedb.com/