The window_spec clause in sql_yacc.yy has a shift/reduce conflict.
In a query like this:
It's not clear what rows stands for. It can be ident in opt_window_ref:
or the ROWS keyword in window_frame_units:
The conflict happens because ROWS is a non-reserved keyword in MariaDB.
- Make ROWS a reserved keyword, as in the SQL standard
- Or change the ident part in opt_window_ref to a new rule ident_window_ref which will not include ROWS.