Thread

Re: Raw parse tree is not dumped to log

Tender Wang <tndrwang@gmail.com> — 2025-08-01T06:24:33Z

Chao Li <li.evan.chao@gmail.com> 于2025年8月1日周五 13:44写道：

> Hi,
>
> When "debug_print_parse" is "on", only the Query structure tree is
> dumped, the raw parse tree is not dumped to log. In some cases, viewing raw
> parse trees are also helpful. It is very hard to view a tree by watching
> variables in a debugger, so I added the following code in my local:
>

When I debug the code, I care more about Query structure,
debug_print_parse is enough for me.
In the debugger, various tools are available, including nodeToString() and
Python scripts.
I usually use the gdbpg tools in [1]. But it was too old. It can't support
the newest version well.

[1] https://github.com/tvondra/gdbpg


>
> diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
> index 0cecd464902..ff456d1d94e 100644
> --- a/src/backend/tcop/postgres.c
> +++ b/src/backend/tcop/postgres.c
> @@ -649,6 +649,10 @@ pg_parse_query(const char *query_string)
>
>         TRACE_POSTGRESQL_QUERY_PARSE_DONE(query_string);
>
> +       if (Debug_print_parse)
> +               elog_node_display(LOG, "raw parse tree",
> raw_parsetree_list,
> +                                                 Debug_pretty_print);
> +
>         return raw_parsetree_list;
>  }
>
> Before submitting this trivial patch, I still want to confirm with the
> community if it's intentional to not dump raw parse tree? If we really
> don't want to dump raw parse tree again "debug_print_parse", are you ok to
> add a new option "debug_print_raw_parse"?
>

If you want to add this, I prefer to  "debug_print_raw_parse". You should
also add documentation to explain this new GUC.



-- 
Thanks,
Tender Wang