SQL Syntax

Examples can be found in the unit tests (query_optimizer/tests/execution_generator/Select.test)

SELECT sum(avg(int_col) OVER w) FROM test
WINDOW w AS
(PARTITION BY char_col
 ORDER BY long_col
 ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW);

Explanation

Each window query will have an OVER keyword which can immediately reference a WINDOW clause or immediately define the WINDOW clause.

Limitations

At the time of writing, the only supported aggregation is AVG. 

This is implemented in a single thread mode. There has not been an attempt to make it support multithreaded environments.