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Can't copy between 2 Postgres databases using COPY FROM DATABASE

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
postgresql
Domain
databases

Research direction

Start by reproducing COPY FROM DATABASE between PostgreSQL 14 and 15 through the DuckDB CLI, including the SCHEMA option. Trace why the operation generates CREATE INDEX orders_pkey ON public.orders() for the shown table. Done means schema and data copying no longer produce an empty index column list.

Written by the indexing model from the issue text.

Description

What happens?

I have attached 2 Postgres databases (PG14 and PG15) and able to run queries on both databases. PG15 database is empty and does not have any tables. When I run the following statement, I get an error:

COPY FROM DATABASE pg14 TO  pg15;

Invalid Error: Failed to execute query "CREATE INDEX orders_pkey ON public.orders()": ERROR:  syntax error at or near ")"
LINE 1: CREATE INDEX orders_pkey ON public.orders()
                                                  ^

D show orders;
┌──────────────┬───────────────┬─────────┬─────────┬─────────┬─────────┐
│ column_name  │  column_type  │  null   │   key   │ default │  extra  │
│   varchar    │    varchar    │ varchar │ varchar │ varchar │ varchar │
├──────────────┼───────────────┼─────────┼─────────┼─────────┼─────────┤
│ order_id     │ INTEGER       │ NO      │ PRI     │         │         │
│ customer_id  │ INTEGER       │ YES     │         │         │         │
│ order_date   │ DATE          │ YES     │         │         │         │
│ product_id   │ INTEGER       │ YES     │         │         │         │
│ notes        │ VARCHAR       │ YES     │         │         │         │
│ total_amount │ DECIMAL(10,2) │ YES     │         │         │         │
└──────────────┴───────────────┴─────────┴─────────┴─────────┴─────────┘

I tried to copy the schema only using the query below and got the same error:

COPY FROM DATABASE pg14 TO  pg15 (SCHEMA);
To Reproduce

Create the same table with the same table structure and try copying between 2 postgres hosts.

OS:

macOS

PostgreSQL Version:

14 and 15

DuckDB Version:

1.1.0

DuckDB Client:

CLI

Full Name:

Arash Nikoo

Affiliation:

Akamai

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
375
Forks
113
Avg merge
5h 32m
Merged PRs (30d)
36

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