Re: Virtual generated columns

Peter Eisentraut <peter@eisentraut.org>

From: Peter Eisentraut <peter@eisentraut.org>

To: Dean Rasheed <dean.a.rasheed@gmail.com>

Cc: pgsql-hackers <pgsql-hackers@postgresql.org>, jian he <jian.universality@gmail.com>

Date: 2025-02-04T22:36:09Z

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

Attachments

v14-0001-Virtual-generated-columns.patch (text/plain) patch v14-0001
v14-0002-Fixup-review-Shlok-Kyal-2025-01-28.patch (text/plain) patch v14-0002
v14-0003-Fixup-review-Dean-Rasheed-2025-01-27.patch (text/plain) patch v14-0003

On 27.01.25 13:42, Dean Rasheed wrote:
> On Mon, 27 Jan 2025 at 09:59, Peter Eisentraut <peter@eisentraut.org> wrote:
>>
>> Here is an updated patch that integrates the above changes and also
>> makes some adjustments now that the logical replication configuration
>> questions are resolved.  I think this is complete now.
>>
> 
> In struct ResultRelInfo, the following field is added:
> 
>      int         ri_NumGeneratedNeededI;
>      int         ri_NumGeneratedNeededU;
> 
> +   /* true if the above have been computed */
> +   bool        ri_Generated_valid;
> +
> 
> but that doesn't really seem to be accurate, because it's set to true
> by ExecInitGenerated() whether it's called with CMD_INSERT or
> CMD_UPDATE, so it will be true before both the other fields are
> computed. It's used from ExecGetExtraUpdatedCols() as an indicator
> that ri_extraUpdatedCols is valid, but it looks like that might not be
> the case, if ExecInitGenerated() was only called with CMD_INSERT.
> 
> I'm not sure if that represents an actual bug, but it looks wrong. It
> should perhaps be called "ri_extraUpdatedCols_valid", and only set to
> true when ExecInitGenerated() is called with CMD_UPDATE, and
> ri_extraUpdatedCols is populated.

Yeah, this is quite contorted.  I have renamed it like you suggested.