Re: Replacement Selection

> in puttuple_common(), the transition from an internal to external sort is
> performed at the bottom of the TSS_INITIAL case in the main switch
> statement.

The transition? Do we internal sort somewhere else and then external sort
here in tuplesort.c?

> The function dumptuples() heapifies the in-core tuples (divides the
> in-core tuples into initial runs and then advances the state to
> TSS_BUILDRUNS).

Cannot see where dumptuples() "advances the state to TSS_BUILDRUNS".
I expected something like
state->status = TSS_BUILDRUNS;
executed through dumptuples()

>
> I recommend you run the code in the debugger on a external-sorting query:
> watch two or three tuples go into the heap and you'll get the idea.
>
> The top of the heap is at state->memtuples[0] the heap goes down from
> there. New tuples are added there and the heap is adjusted (Using the
> tuplesort_heap_siftup() function).
>
> -Tim
>