Feature Request: Output EXPLAIN in Postgres format

[dpxcc]

Why do you want this feature?

Currently, the EXPLAIN output is in DuckDB format, which tends to be lengthy and doesn't integrate well with Postgres
It would be more user-friendly to have the EXPLAIN output in a Postgres-like format

I noticed that DuckDB allows specifying the EXPLAIN output format

D EXPLAIN (FORMAT TEXT) SELECT a FROM t;

┌─────────────────────────────┐
│┌───────────────────────────┐│
││       Physical Plan       ││
│└───────────────────────────┘│
└─────────────────────────────┘
┌───────────────────────────┐
│         SEQ_SCAN          │
│    ────────────────────   │
│             t             │
│                           │
│       Projections: a      │
│                           │
│          ~0 Rows          │
└───────────────────────────┘


D EXPLAIN (FORMAT JSON) SELECT a FROM t;

┌─────────────────────────────┐
│┌───────────────────────────┐│
││       Physical Plan       ││
│└───────────────────────────┘│
└─────────────────────────────┘
[
    {
        "name": "SEQ_SCAN ",
        "children": [],
        "extra_info": {
            "Text": "t",
            "Projections": "a",
            "Estimated Cardinality": "0"
        }
    }
]

So one possible implementation could involve generating the output in JSON format first and then formatting it to resemble Postgres

[wuputah]

Yes, this was the intention; we collaborated with DuckDB to get the EXPLAIN support in JSON added, but we haven't gotten around to implementing this in pg_duckdb. PR would be welcome here.