Saturday, September 15, 2012

Elisp utility to open SQLplus from a remote host

If you are in a situation when you have to login to an intermediate or jump host to open SQLplus session to your database, here is a utility that you can make use of. You can store this utility in your .emacs file. Then the utility can be invoked interactively from inside Emacs, by typing "Alt-x open-remote-sqlplus-session-interactive".

With autocmpletion, you can specify the session alias that you would like to open.

To make the best use of the utility, you need to specify the list of jump hosts and the SQLplus connection strings in the "alias-to-jumphosts-alist" variable. If you need to run any custom commands immediately after opening SQLplus session (in addition to commands in your login.sql or glogin.sql files), you can add these commands in list-of-sqlplus-setup-commands.

I find this utility to be a tremendous time saver. Hope you also find it the same way.

Here is the utility as a gist:

Saturday, September 08, 2012

Have a timestamp, for Christ's sake!

This post is an appeal to all the developers and content writers. Please take it seriously. Let us help each other by following the simple guideline of timestamping each artifact that is produced.

Whenever you encounter an issue, or while troubleshooting a problem, what is the first thing you do? I just copy and paste the error message in Google and search if someone else have encountered the same problem and if a resolution is available. Sometimes I get conflicting resolutions showing up in the Google results. For e.g. one site might suggest me to perform task A to resolve the problem, while another site might suggest to perform task B. If I have time, I will try each one of them until the issue is resolved. But unfortunately I find it a terrible waste of my time. Instead of appreciating the good intention of the author to share his wisdom, I end up cursing the person.

Why? The reason most of the times is very simple. Those articles don't have a date and time about when they were published. Most of the time, I find that the most recent ones are accurate. Rarely it might be otherwise too. Think how many times you have gone back and updated your old entries when your suggested method will no longer work! In my case, almost none. So, unless someone have a time of reference, they will not be able to compare two solutions to decide which one might be more recent.

So I appeal to all the developers and content writers this:
Please produce all your contents with both date and time. Timestamp all the artifacts that you produce. This will tremendously help everyone and save a lot of time.
Please don't publish an article just with time alone (like "Sun 12:00 PM", as you might find in most of the blogs!). It is just as useless as not having the timestamp at all.

With HTML5's time tag, you can also help the search engines to identify when the artifact was actually produced.

Thursday, September 06, 2012

Who invented email?

Sometime back I received a link in my Facebook account shared by one of my friends which claims that Mr. V.A. Shiva Ayyadurai is the one who invented email. My first reaction was WTH? As far as I know, email existed since early 70s. As per the article, Mr. Ayyadurai invented email  in 1978. I spent a lot of time in that website reading through all the documents and verifying how far it is true. To the best of my knowledge, as per the documented evidence, I am convinced that Mr. Ayyadurai is the inventor of email.

But just around the same time, another link surfaced in Hacker News, with the title "Email Will Never Die - The Man Who Invented It Reveals Why". The article wrongly claims that Mr. Ray Tomlinson was the one who invented email in 1971. While I hold high respect for the hacks of Mr. Tomlinson to send a file from one machine to another machine, the SNDMSG program by no way comes close to the email as we know it today. Worse, until the end of the article, the article doesn't give a single point that substantiates WHY email will never die. The article in itself is too shallow.

Here are my reasons/opinions why Mr. Tomlinson did not invent email.

  1.  To my knowledge, the term email doesn't appear anywhere in literature around early 1970s. In fact, the term doesn't even show up in the first RFC for SMTP published in 1982 (which is the protocol used to send mail messages). You can check that here. Then how can you claim that someone invented email in 1971?
  2. Suppose I wrote a program in 1970s that copied a piece of text from user1@host1 to user2@host2. Later someone comes up with email which also copies a piece of text from user1@host1 to user2@host2. Hence can I claim that I invented email?
  3. What most of us have understood as email is way too different than the messaging systems that existed in the early systems. The RFC 196 provided as a reference in Mr. Tomlinson's web page, doesn't resemble the email systems we use today. For e.g. that RFC or the RFC that obsoletes that doesn't talk about organizing mails in folders (like inbox, sent, etc.) which was first used by the system designed by Mr. Ayyadurai.
  4. It feels like there is a lot of shallow PR cry by BBN. This is a company that has vested interest in claiming to be the first to have invented email.
In summary, give credit where its due. Its a shame that when I submitted a comment for the article with my thoughts, my comment was censored by the author. Hence this article.