Re: Virtual generated columns

Peter Eisentraut <peter@eisentraut.org>

From: Peter Eisentraut <peter@eisentraut.org>

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

Cc: pgsql-hackers <pgsql-hackers@postgresql.org>, Dean Rasheed <dean.a.rasheed@gmail.com>

Date: 2025-01-14T09:58:20Z

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 →

Expand virtual generated columns for ALTER COLUMN TYPE
- 5069fef1cfae 18.0 landed
Eliminate code duplication in replace_rte_variables callbacks
- 363a6e8c6fcf 18.0 landed
Expand virtual generated columns in the planner
- 1e4351af329f 18.0 landed
Virtual generated columns
- 83ea6c54025b 18.0 landed
Additional tests for stored generated columns
- 41084409f635 18.0 landed
Improve generated_stored test
- 44b61efb7928 18.0 landed
- 86749ea3b766 18.0 landed
Fix handling of CREATE DOMAIN with GENERATED constraint syntax
- 84a67725cd11 18.0 landed
Add pg_constraint rows for not-null constraints
- 14e87ffa5c54 18.0 cited
Put generated_stored test objects in a schema
- 894be11adfa6 18.0 landed
Rename regress test generated to generated_stored
- b9ed4969250d 18.0 landed
Small code simplification
- 7ff9afbbd1df 18.0 landed
Remove useless code
- e26d313bad92 18.0 landed
Remove useless initializations
- da2aeba8f533 18.0 landed
doc: Clarify that pg_attrdef also stores generation expressions
- da486d360103 18.0 landed
Clean out column-level pg_init_privs entries when dropping tables.
- 76618097a6c0 17.0 cited
Re-implement the ereport() macro using __VA_ARGS__.
- e3a87b4991cc 13.0 cited

On 09.01.25 13:41, jian he wrote:
> we can not ALTER COLUMN DROP EXPRESSION for virtual for now.
> so the following comments in generated_virtual.sql conflict with the output.
> ```
> -- check that dependencies between columns have also been removed
> ALTER TABLE gtest29 DROP COLUMN a;  -- should not drop b
> \d gtest29
> ```
> we can also comment out line 557 in generated_virtual.sql.

Ok will do.

> attach patch is removing unnecessary parentheses from
> ```ereport(ERROR, (errcode```
> only for this patch related.
> per commit https://git.postgresql.org/cgit/postgresql.git/commit/?id=e3a87b4991cc2d00b7a3082abb54c5f12baedfd1
> 
> also https://www.postgresql.org/docs/current/error-message-reporting.html says
>   ""The extra parentheses were required before PostgreSQL version 12,
> but are now optional.""

Right.  I tried to keep it mostly consistent with existing surrounding 
code, but I will do another pass to improve that.