Archive for the ‘database’ Category

All in days of work

Saturday, September 13th, 2008




Sometime, the GPRS coverage & priority issue is a turning down subject in our AVLS operations. Despite of GPS data errors and interferences, we choose to add SMS  mode for failsafe function to our AVLS architecture. It’s not really a big deal to develope the back engine, but in considering the alarm dispacthing functions. Maybe, it will become another turning down factor in our bussiness. the dispatcher should be really intelligent to determine the raw data despite of many of uncertainty factors that always bother. We bought a quad-core dell 1U rack server in order to replace our old beloved application server, a 4 pentium 4 Dell 5U tower server. We done doing upgrades to database server, and now working on the back-end & front-end application test. In another hand, we are migrating the Telemery System for waterworks…. developing a friendly GUI for Flood Monitoring System plus testing the alarm dispatching functions, still handling data loses in ABB EM meters integrations… sigh!

Database migration tool: I wish I found LiquiBase earlier

Sunday, August 10th, 2008



LiquiBase — available since 2006 — is an open source, freely available tool for migrating from one database version to another (see Resources). A handful of other open source database-migration tools are on the scene as well, including openDBcopy and dbdeploy. LiquiBase supports 10 database types, including DB2, Apache Derby, MySQL, PostgreSQL, Oracle, Microsoft® SQL Server, Sybase, and HSQL.

A year ago, we’ve gone through a painstaking database & system migration from PostgreSQL to MSSQL. We’ve never found this tool. Maybe, we will try to use this tool next time… if any. 😀

Link: IBM

Change the default PostgreSQL data directory on Windows

Monday, May 19th, 2008

pgsql logoOur database which is storing every minute telemetry data is now getting bigger and need to be relocated to another newly mounted drive. So, I need to relocate the old data to a new disk. Actually, I don’t need to do this if my drive is a dynamic drive.

As we already know, PostgresSQL for Windows installs the PGDATA directory by default into “C:\Program Files\PostgreSQL\8.3\data”. This mini-HOWTO explains how to change the default PGDATA directory to another location. Note that 8.3 is the version number of my current PostgreSQL installation. It could be varied based on your installed version. (more…)