Today I realised that I have been programming for 25 years. Quite an anniversary! Of course, it does not really feel like that long, probably because a bit more than the first half of the time was really ‘just for fun’, as a kid’s hobby and later during University. I also realised that right from… Continue reading 25 years of Open Source
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DGCov: A tool for checking test coverage of a patch
Today I published the DGCov tool on the MySQL Forge. DGCov is a neat tool that I implemented last year for use internally at MySQL, an old idea of Monty’s. The idea is to help developers to check that a new patch for the server code has received adequate testing before pushing it to the… Continue reading DGCov: A tool for checking test coverage of a patch
Partitioned archive tables
Is there anyone using partitioned archive tables in MySQL 5.1 for storing logs (or other voluminous data)? Storing large amounts of logs in a relational database can bring special challenges. Logs can take up huge amounts of space on disk, and while disk space is cheap, disk I/O can be expensive, performance-wise. But many logs… Continue reading Partitioned archive tables
Data Corruption!
At the start of this week, we suffered a corruption of our main 5.1 source code repository at MySQL. No data was lost, but I spent most of four working days on cleaning up the corruption, Monty spent one day, and many other people had to spend time on this or were stalled in their… Continue reading Data Corruption!
Suduko solver
There are probably tons of these already available, but here is a quick suduko solver (in Perl): #! /usr/bin/perl # Example: # # echo $’ 2 \n 1 9 4 \n 2 1 5 9\n3 6 \n 68 41 5\n 427 8 \n 51 \n 7 3 \n79 5 ‘| perl suduko-solve.pl # use strict;… Continue reading Suduko solver
Full-index scan faster than full-table scan
At this years LinuxForum I wasmanning the MySQL booth together with Carsten Pedersen. We were keptquite busy with lots of people coming to tell about their use of the MySQLdatabase for their particular project and ask about or discuss a particularissue of theirs. Which was fine, since the talks did not appeal a lot to… Continue reading Full-index scan faster than full-table scan
Visual Studio limitations
MySQL 5.1 is moving to a new system for building the source code on Windows, based on CMake (more on this another time). While finishing up the last bits of this, I ran into a very annoying limitation in Visual Studio (version 7.1 I think). The library include path in Visual Studio project files (.vcproj)… Continue reading Visual Studio limitations
Free Software and SS7
In my previous job at Sifira A/S, I developed the first version of chan_ss7. Chan_ss7 is a module for Asterisk, which interfaces Asterisk to an SS7 network. So what is SS7? It is the network that runs the worlds telephone network. Chances are that as soon as your phone call reaches the local central (analog/ISDN)… Continue reading Free Software and SS7