Assertion failed: types == input.GetTypes() in column_data_collection.cpp, line 718

[Timmmm]

Unfortunately this is with proprietary data so I can't give a full reproducer but I do these queries with duckdb-rs 0.9.2:

• CREATE TABLE queue as SELECT * FROM read_json_auto('example.json');
• SELECT DISTINCT ON (account) * FROM queue;

It works fine in the DuckDB CLI but from my Rust code I get this error:

Assertion failed: types == input.GetTypes(), file C:\Users\Tim\.cargo\registry\src\index.crates.io-6f17d22bba15001f\libduckdb-sys-0.9.2\duckdb\src/common/types/column/column_data_collection.cpp, line 718

Unfortunately RUST_BACKTRACE=1 doesn't give any more info (presumably because it is a C++ assertion, not Rust).

Any idea what could be causing this?

[mlafeldt]

Thanks for the report.

This assertion lives in DuckDB core (column_data_collection.cpp), not in the Rust bindings. It's an internal type mismatch check during DISTINCT ON materialization, so it was a DuckDB 0.9.2 bug rather than a duckdb-rs issue.

It appears to be fixed by upstream. I couldn't reproduce it on the current bundled DuckDB (v1.5.3).