[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <YQakDYRnId+bK+ue@lx-t490>
Date: Sun, 1 Aug 2021 15:39:25 +0200
From: "Ahmed S. Darwish" <a.darwish@...utronix.de>
To: Steven Rostedt <rostedt@...dmis.org>
Cc: linux-trace-devel@...r.kernel.org, linux-kernel@...r.kernel.org,
Tom Zanussi <zanussi@...nel.org>,
Daniel Bristot de Oliveira <bristot@...hat.com>,
Masami Hiramatsu <mhiramat@...nel.org>,
Namhyung Kim <namhyung@...nel.org>,
linux-rt-users <linux-rt-users@...r.kernel.org>,
Clark Williams <williams@...hat.com>
Subject: Re: [PATCH 17/17] libtracefs: Add man page for tracefs_sql()
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
Powered by blists - more mailing lists