One goofy SELECT can freeze the computer hard

[manticore-projects]

Greetings!

I do understand well the memory constraints and what happens when you cross-multiply large tables. I also understand, that DuckDB gives the power to its user to set the memory correctly. So far so good.

However, I just froze my linux machine -- twice! -- by running an unlimited cross select -- and I feel like this should not happen, especially when running in/from a Java environment (although its just a JNI bridge really).

Example is Amazon Redshift's TickDB:

are@ryzen ~ [1]> duckdb Documents/JSQLTranspiler/.manticore/JSQLTranspilerTest.duckdb 
v0.10.3 70fd6a8a24
Enter ".help" for usage hints.
D select count(*) from sales
  ;
┌──────────────┐
│ count_star() │
│    int64     │
├──────────────┤
│       172456 │
└──────────────┘

D select count(*) from listing;
┌──────────────┐
│ count_star() │
│    int64     │
├──────────────┤
│       192497 │
└──────────────┘

If I run the following statement via JDBC, my computer freezes hard. I can't even get to the terminal or login via SSH:

SELECT  numtickets
        , priceperticket
        , totalprice
        , listtime
FROM sales
    , listing
-- LIMIT 10
;

Activating the LIMIT 10 of course remedies the situation.

Now I wonder: Why would it freeze like that instead of obeying the available memory and/or why would the JDBC call not set a safety DuckDB memory limit (e.g. based on -Xmx as a good benchmark figure)?