Thread: How to find the final transformed query in postgresql

How to find the final transformed query in postgresql

From
Goti
Date:
Hi Geeks,

Env: postgres12

I am new to postgres and coming from an Oracle background. Please excuse me if I am not asking valid questions.

 I would like to know if postgres performs any transformations when it does the parsing? If yes, is there a way we can get the final transformed query?

Thanks,

Goti

Re: How to find the final transformed query in postgresql

From
Tom Lane
Date:
Goti <aryan.goti@gmail.com> writes:
>  I would like to know if postgres performs any transformations when it does
> the parsing?

This might be helpful reading:

https://www.postgresql.org/docs/current/overview.html

> If yes, is there a way we can get the final transformed query?

See debug_print_parse and friends [1].  Depending on what you mean by
"final transformed query", you might instead want debug_print_rewritten,
or maybe you want the plan, in which case EXPLAIN is a much friendlier
way to look at it than debug_print_plan.

            regards, tom lane

[1] https://www.postgresql.org/docs/current/runtime-config-logging.html#RUNTIME-CONFIG-LOGGING-WHAT



Re: How to find the final transformed query in postgresql

From
Goti
Date:
Thanks a lot Tom.

Thanks,

Goti


On Mon, Apr 18, 2022 at 7:43 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
Goti <aryan.goti@gmail.com> writes:
>  I would like to know if postgres performs any transformations when it does
> the parsing?

This might be helpful reading:

https://www.postgresql.org/docs/current/overview.html

> If yes, is there a way we can get the final transformed query?

See debug_print_parse and friends [1].  Depending on what you mean by
"final transformed query", you might instead want debug_print_rewritten,
or maybe you want the plan, in which case EXPLAIN is a much friendlier
way to look at it than debug_print_plan.

                        regards, tom lane

[1] https://www.postgresql.org/docs/current/runtime-config-logging.html#RUNTIME-CONFIG-LOGGING-WHAT