Florent Clairambault

LinQ to Entities on ADO.Net vs LinQ to SQL

Overview To make it short : LinQ to SQL only works with SQL Server but it’s working great. It’s simple, supports all LinQ operations and optimizes the generated SQL queries. LinQ to Entities on ADO.Net works with lots of database but it doesn’t behave like LinQ to SQL and doesn’t support some key LinQ features. Now the long story : For the last project I’ve been working on, we wanted to use LinQ and still be able to switch to one database to an other (MSSQL to MySQL for instance).

MySQL Master-Master desynchronization

Settings a master-master synchronization is pretty easy. You can find a quick guide to do this on google, just try. What is a little bit more problematic is when you lose your loved sync. And that can happen. It happened to me yesterday, I upgraded my two servers from Debian 4.0 to Debian 5.0. The reason is that the old version (something like 5.0.32) used the Relay_Log_File ${hostname}-relay-bin.XXXXXX. And the new version (5.

Etrange MySQL

Aujourd’hui, j’ai décidé d’optimiser une recherche MySQL de recherche par proximité de points spatiaux. En effet, j’avais une requête qui prenait 250 ms en moyenne. Je recherche donc quelques infos et là, bonne surprise je tombe sur un document issu de l’entreprise MySQL sur le sujet. En utilisant l’optimisation qu’ils recommandent (par approximation préalable en un carré de recherche), j’arrive à réduire les requêtes à des temps allant de 5 à 35 ms.