Build MySQL from source with debug enabled

[Zhan Li]

Hi All,

I'm building mysql-5.6.16 from source on RedHat. I was wondering how to enable debug option so that the DBUG statements in the source code would be executed?

To be more specific, in sql_planner.cc file, there's DBUG_EXECUTE() in greedy_search() as following:

DBUG_EXECUTE("opt", print_plan(join, n_tables, record_count, read_time, read_time, "optimal"););

I'd like to see the printed out "optimal plan", what should I do? Thanks.

Cheers,
Zhan