Horton

Re: Virtual generated columns

Peter Eisentraut <peter@eisentraut.org>

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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: 2024-11-12T16:09:35Z
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 →

  1. Expand virtual generated columns for ALTER COLUMN TYPE

  2. Eliminate code duplication in replace_rte_variables callbacks

  3. Expand virtual generated columns in the planner

  4. Virtual generated columns

  5. Additional tests for stored generated columns

  6. Improve generated_stored test

  7. Fix handling of CREATE DOMAIN with GENERATED constraint syntax

  8. Add pg_constraint rows for not-null constraints

  9. Put generated_stored test objects in a schema

  10. Rename regress test generated to generated_stored

  11. Small code simplification

  12. Remove useless code

  13. Remove useless initializations

  14. doc: Clarify that pg_attrdef also stores generation expressions

  15. Clean out column-level pg_init_privs entries when dropping tables.

  16. Re-implement the ereport() macro using __VA_ARGS__.

On 12.11.24 09:49, jian he wrote:
>> On Wed, Nov 6, 2024 at 12:17 AM Peter Eisentraut <peter@eisentraut.org> wrote:
> RelationBuildPartitionKey
> if (!isnull)
> {
>          char       *exprString;
>          Node       *expr;
>          exprString = TextDatumGetCString(datum);
>          expr = stringToNode(exprString);
>          pfree(exprString);
>          expr = expand_generated_columns_in_expr(expr, relation);
> }
> no need expand_generated_columns_in_expr?
> in ComputePartitionAttrs, we already forbidden generated columns to be
> part of the partition key.

True.  I have removed this extra code in v9.

> check_modified_virtual_generated, we can replace fastgetattr to
> heap_attisnull? like:
>              // bool        isnull;
>              // fastgetattr(tuple, i + 1, tupdesc, &isnull);
>              // if (!isnull)
>              //     ereport(ERROR,
>              //             (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
>              //              errmsg("trigger modified virtual generated
> column value")));
>              if (!heap_attisnull(tuple, i+1, tupdesc))
>                  ereport(ERROR,
>                          (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
>                           errmsg("trigger modified virtual generated
> column value")));

I don't know.  fastgetattr() is supposed to be "fast". ;-)  It's all 
inline functions, so maybe that is actually correct.  I don't have a 
strong opinion either way.