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Displaying posts with tag: command line (reset)
Quick benchmarking trick

I have been doing quite a lot of benchmarking recently.
I needed to find a safe way of measuring the time spend by the database doing a long task, like catching up on a huge backlog of accumulated replication updates. The problem with measuring this event is that I can record when it starts, but I can't easily detect when it finishes. My initial approach was to monitor the database and count the tables rows to see when the task was done, but I ended up affecting the task performance with my additional queries. So I thought of another method.
Since I had control on what was sent from the master to the slave, I used the following:
The initial time is calculated as the minimum creation time of the databases that I know are created during the exercise. Let's say that I had 5 databases named from db1 to db5:

set @START = (select min(create_time) from information_schema.tables where table_schema like "db%")

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A cool terminal tip for Mac users

If you use a Mac, and you are dealing with many similar tasks at once, like examining many database servers in different terminals, you may like this one.
I have been using iTerm 2 for a while, and my handling of parallel tasks has improved a lot. (No, I am not talking about Parallel replication, although I have applied this trick while testing that technology as well.)
iTerm2 has some cool features, and probably the most striking one is split panes. That alone would be a good reason for giving iTerm2 a try. But the one that I use the most, often in combination with Split Panes, is called Send Input to all tabs.
Here is how it works.
Let's say I need to …

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Welcome googleCL
I am writing this blog post with Vim, my favorite editor, instead of using the online editor offered by blogger. And I am uploading this post to my Blogger account using Google CL a tool that lets you use Google services from the command line.
I am a command line geek, and as soon as I saw the announcement, I installed it in my laptop. The mere fact that you are reading this blog post shows that it works.

GoogleCL is an apparently simple application. If you install it on Mac using macports you realize how many dependencies it has and how much complexity it gives under the …

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Sometimes, even a command line guy likes a GUI

As everyone knows, I am a command line guy. I am very much comfortable with the shell prompt and the command line SQL client. I do most of my work that way, and I am very much productive.
However, there comes a time when even for a command line enthusiast a GUI can be helpful.
Here comes the latest MySQL Workbench 5.2.
There are two areas where I feel that WB can give me a hand:
The first is when looking at tables that contain BLOB columns. Sure I can deal with them at the command line, but this editor makes my life easier.

When a column contains a BLOB, you can open the field viewer.

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How to get colored output from ‘ls’ on Solaris10

For all of those linux users out there that have moved over to, or tried out, Solaris10 or OpenSolaris because they heard the tales of how MySQL is faster on Solaris… or perhaps you wanted to learn how to use Sol10 for the great features of Zones or the ZFS filesystem? Regardless of why you’re on it you are probably wondering why Linux has colored output of filenames and directories but Solaris does not. The question of ‘why?’ isn’t important, but how to enable colors is. It’s very simple, and here’s how I fixed it. This is a result of digging through multiple semi-related links on Google.

  1. Download all packages from
    • dependency: libintl-3.4.0-sol10-x86-local
    • dependency: libiconv-1.13.1-sol10-x86-local
    • dependency: gmp-4.2.1-sol10-x86-local
    • dependency: gcc-3.4.6-sol10-x86-local or libgcc-3.4.6-sol10-x86-local depending on your …
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Another command line tip

Encouraged by Baron Schwartz tip on result set comparison, here are a few more, on the same vein.
First, you can send a result set to a file. Probably you will say "yeah, I know, using SELECT INTO OUTFILE". Correct. Except that you can't rewrite to an existing file, if you want to, and you will get a raw output, not the well formatted one that you usually see on the command line. For example:

mysql > select 1 into outfile '/tmp/f1.txt';
mysql > \! cat /tmp/f1.txt

mysql > select 1 into outfile '/tmp/f1.txt';
ERROR 1086 (HY000): File '/tmp/f1.txt' already exists

BTW, \! command is a handy shortcut for executing a shell command.
Let's see what happens with the …

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