Is there any performance benefit to minifying MySQL queries? I recently ran across some tools that help you minify queries, and I'm curious to know if that's actually something that could help performance.
I'm going to post an answer just to put an end to this bizarre debate. 

TLDR: No, "minification" will not provide any performance benefit that you would notice.

"Minification" refers to a process of removing any optional whitespace from a program source code and giving program identifiers (variables, functions, etc.) shortest possible names, all while retaining the original semantics of the program. The original purpose of it was to reduce the download time of JavaScript code embedded in (or linked from) HTML pages, with the aim of improving user experience on many web sites. As a side effect, minified JavaScript code is practically unreadable by humans, which brought about the secondary usage of the practice, that of obfuscating the source code, often for malicious purposes.

SQL statement syntax differs from other programming languages in that it rarely has any variables1; it contains mostly keywords and SQL object identifiers, which obviously cannot be replaced by arbitrary shorter tokens without stripping a statement entirely of its meaning. That leaves only two minification targets: optional whitespace and, possibly, correlation names when such are used, which makes minification "improvement", in terms of the overall statement length, significantly less impressive.

Further, unlike transferring sources of HTML pages over long range internet links from web servers to residential clients, the part of the overall SQL statement processing cycle that can be theoretically improved by reducing the length of the statement string is negligible, compared to other steps, such as optimizing the statement, executing it, and sending statement results back to the client, if applicable. Besides, SQL statements normally travel over backbone networks, which are much faster and experience much less contention than public internet.

Finally, if you decide to apply minification to dynamically composed SQL statements, you might even see overall performance degradation, because a poorly written minification code2 will probably have overhead that  outweighs whatever "benefits" it produces.

As a result, you3 are unlikely to perceive any difference in effective statement processing time (from submission to receiving first results) between minified and non-minified statements.



1 - PSM and compound SQL statement code can, of course, contain variable names, but in the cases when such code is used, potential network throughput improvements from minification are even less significant.
2 - I would find it doubtful that people engaging in such practice can produce high quality code.
3 - Yes, even if you are developing a High Frequency Trading application.