Re: CAST(... ON DEFAULT) - WIP build on top of Error-Safe User Functions

jian he <jian.universality@gmail.com>

From: jian he <jian.universality@gmail.com>

To: Vik Fearing <vik@postgresfriends.org>

Cc: Corey Huinker <corey.huinker@gmail.com>, Isaac Morland <isaac.morland@gmail.com>, pgsql-hackers@lists.postgresql.org

Date: 2025-07-22T10:19:18Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Make cast functions to type money error safe
- b36b95640487 19 (unreleased) landed
Make cast function from circle to polygon error safe
- 26f9012beecf 19 (unreleased) landed
Make geometry cast functions error safe
- 45cdaf3665be 19 (unreleased) landed
Make cast functions from jsonb error safe
- 10e4d8aaf46f 19 (unreleased) landed
Make many cast functions error safe
- e2f289e5b9b8 19 (unreleased) landed
Add SQL/JSON query functions
- 6185c9737cf4 17.0 cited
Add soft error handling to some expression nodes
- aaaf9449ec6b 17.0 cited

On Tue, Jul 22, 2025 at 2:45 PM Vik Fearing <vik@postgresfriends.org> wrote:
>
> It was accepted into the standard after 2023 was released.  I am the
> author of this change in the standard, so feel free to ask me anything
> you're unsure about.
>

is the generally syntax as mentioned in this thread:
CAST(source_expression AS target_type DEFAULT default_expression ON ERROR)

if so, what's the restriction of default_expression?