Date: 2019-10-09 22:40:52 +0200
From: @swingbit
To: SQL devs <>
Version: 11.33.11 (Apr2019-SP1)
CC: @mlkersten, @PedroTadim

Last updated: 2019-11-28 10:00:06 +0100

Comment 27352

Date: 2019-10-09 22:40:52 +0200
From: @swingbit

User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.132 Safari/537.36
Build Identifier:

When using TRACE a user expects to see the trace for that specific query.
Instead, the output includes traces all active sessions at that moment. That is highly confusing and has possible privacy/security issues.

Reproducible: Always

Steps to Reproduce:

(shell 1)$ yes "SELECT 'I am from session 1';" | mclient -f trash -d demo
(shell 2)$ yes "SELECT 'I am from session 2';" | mclient -f trash -d demo
(shell 3)$ echo "TRACE SELECT 'I am from session 3';" | mclient -d demo

Repeat command from shell 3. Every time it gives a different output, with content from the other sessions.

Comment 27353

Date: 2019-10-10 16:30:56 +0200
From: @mlkersten

Returning global TRACE information as part of the result set is likely to be abandoned soon. The purpose of it was to get a complete picture on what is going on in the server. Because, the performance of a single query may be affected by concurrent queries.

Indeed, an overview of all activities may disclose more information then required.

Comment 27364

Date: 2019-10-15 15:19:59 +0200
From: @PedroTadim

With the latest changes on default branch, this should no longer be an issue.

Comment 27365

Date: 2019-10-15 15:39:10 +0200
From: @mlkersten

The Default branch contains better code to separate the profiler events