Re: [PATCH 17/17] libtracefs: Add man page for tracefs_sql()

[Ahmed S. Darwish]

On Fri, Jul 30, 2021, Steven Rostedt wrote:
> +
> +The SQL format is as follows:
> +
> +*SELECT* <fields> FROM <start-event> JOIN <end-event> ON <matching-fields> WHERE <filter>
> +
> +Note, although the examples show the SQL commands in uppercase, they are not required to
> +be so. That is, you can use "SELECT" or "select" or "sElEct".
> +

Maybe it would be helpful to mention that, unlike normal SELECT queries,
the JOIN and ON parts above are _not_ optional?

That is, generic "one event source" queries:

  SELECT common_pid,msr,val FROM write_msr WHERE msr=72

are not supported. (I wish they were though ;-))

BTW, thanks a lot for this work. It will finally make synthetic events
usable!

Kind regards,

--
Ahmed S. Darwish
Linutronix GmbH