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ERROR: deletes on append-only tables are not supported in serializable transactions

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
postgres, python
Domain
databases

Research direction

Start by reproducing the direct DELETE and the postgres_execute call against Greenplum 7.1 (PostgreSQL 12.12), using DuckDB 1.0.0 from Python 3.9. Compare the transaction behavior and trace the postgres_execute entry point. Done means confirming the cause of the serializable append-only-table error and documenting or fixing the supported behavior.

Written by the indexing model from the issue text.

Description

What happens?

ERROR: deletes on append-only tables are not supported in serializable transactions

To Reproduce

I am computing in DuckDB and then writing the results back to Greenplum. Before writing, I need to delete existing data, but I tried two methods:

delete from gp.dm.fct_sale_stockorg_kpi 
where day_date > ('2024-07-04'::timestamp - '40 day'::interval) and day_date <= ('2024-07-04'::timestamp)

method2:

call postgres_execute('gp',$gp$
delete from dm.fct_sale_stockorg_kpi 
where day_date > ('2024-07-04'::timestamp - '40 day'::interval) and day_date <= ('2024-07-04'::timestamp)
$gp$)

the first method is very slow,
and the second method gives an error as described in the title.
why?

OS:

centos7

PostgreSQL Version:

gp7.1(pg12.12)

DuckDB Version:

1.0.0

DuckDB Client:

python3.9

Full Name:

wang cz

Affiliation:

Linezone

Have you tried this on the latest main branch?
  • I agree
Have you tried the steps to reproduce? Do they include all relevant data and configuration? Does the issue you report still appear there?
  • I agree
Dominant language
C++
Stars
373
Forks
112
Avg merge
9h 48m
Merged PRs (30d)
28

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