[feike]

A single query can write to multiple tables, using CTE's in PostgreSQL for example.

You could compose a SQL query that allows you to map multiple resultsets to 1 resultset, although that feels a bit awkward.

    WITH a AS (
        insert into a (k, v) values ('a', 1.0) returning *
    ), b AS (
        insert into b (k, v) values ('b', 2.0) returning *
    )
    SELECT
        row_to_json(a)
    FROM
        a
    UNION ALL
    SELECT
        row_to_json(b)
    FROM
        b;

Returns:

        row_to_json        
    --------------------------
    {"a_id":1,"k":"a","v":1}
    {"b_id":1,"k":"b","v":2}
    (2 rows)

[zasdffaa]

That is eye-opening but - if it actually works and I find it hard to believe - is no way ...

ah, the insert is a CTE because it produces a value ('returning' I guess). Hmm. This is very odd. Doesn't seem to work in mssql.

Well thanks for the can of worms...

[ltbarcly3]

mssql CTE support is very very basic, to the point of being not very useful.

[branko_d]

Good to know, I wasn't aware PostgreSQL supports this.

I'm currently on SQL Server and it doesn't support INSERT as a CTE (and I think most DBMSes out there still don't). It would definitely make my life easier if it did...

[chrisjc]

It's not the only DB or way of doing it either. Snowflake supports multi-table inserts for example:

https://docs.snowflake.com/en/sql-reference/sql/insert-multi...