Wired if-statement in gen_partprune_steps_internal

[Andy Fan]

Hi:

  I found the following code in gen_partprune_steps_internal,  which
looks the if-statement to be always true since list_length(results) > 1;
I added an Assert(step_ids != NIL) and all the test cases passed.
if the if-statement is always true,  shall we remove it to avoid confusion?


gen_partprune_steps_internal(GeneratePruningStepsContext *context,


        if (list_length(result) > 1)
        {
                List       *step_ids = NIL;

                foreach(lc, result)
                {
                        PartitionPruneStep *step = lfirst(lc);

                        step_ids = lappend_int(step_ids, step->step_id);
                }
                Assert(step_ids != NIL);
                if (step_ids != NIL) // This should always be true.
                {
                        PartitionPruneStep *step;

                        step = gen_prune_step_combine(context, step_ids,

      PARTPRUNE_COMBINE_INTERSECT);
                        result = lappend(result, step);
                }
        }


-- 
Best Regards
Andy Fan