Showing entries 1 to 5
Displaying posts with tag: algorithm (reset)
Which Compression Tool Should I Use for my Database Backups? (Part II: Decompression)

On my post last week, I analysed some of the most common compression tools and formats, and its compression speed and ratio. While that could give us a good idea of the performance of those tools, the analysis would be incomplete without researching the decompression. This is particularly true for database backups as, for those cases where the compression process is performed outside of the production boxes, you may not care too much about compression times. In that case, even if it is relatively slow, it will not affect the performance of your MySQL server (or whatever you are using). The decompression time, however, can be critical, as it may influence in many cases the MTTR of your whole system.

Testing …

[Read more]
Running Standard Deviation in MySQL

Calculating the standard deviation in MySQL is a no-brainer by using the build-in aggregate function STDDEV(). If you don't need the original data and only want to save aggregated values in your database, the whole matter is getting more complicated - but is worth from a space and performance point of view.

Read the rest »

Four short links: 28 June 2011
  1. Networks Blocking Google TV -- the networks are carrying over their old distribution models: someone aggregates eyeballs and pays them for access. In their world view, Google TV is just another cable company. They're doubling down on this wholesale model, pulling out of Hulu and generally avoiding dealing with the people who ultimately watch their shows except through ad-filled shows on their corporate sites. (via Gina Trapani)
  2. Mobile Market Snippets -- lots of numbers collected by Luke Wroblewski. After the Verizon iPhone launched …
[Read more]
Analyze online behavior with MySQL and PHP

A useful feature of statistical systems in social networking backend's is the analysis of when members are mostly, or better said, in average online. Imagine, that we have a database table to store DATETIME-timestamps of when users logged in, which could look like this:

Read the rest »

A challenge: partition a character set in MySQL

How good are your SQL and/or general coding skills? I have a specific challenge I'd like your help solving. I am not sure it's possible, but I'd love to be proven wrong.

Showing entries 1 to 5