Showing posts from May, 2011

WSO2 SOA middleware Deployment Tips - 1 - validationQuery to avoid broken DB connections

I thought to put together some best practices, guidelines on deploying WSO2 SOA middleware platform. This post will remind you a well-known best practice used in most of the product deployments. When you are maintaining DB connections, it is always recommended to use a validationQuery to check the health of the TCP connection of the connections stay in DB connection pool. Because the connection opening is an expensive and time consuming operation, after a connection is created, it will be kept open for a specific time in the pool. When re-using these connections from the pool, there can be situations that the TCP connection to the DB is interrupted and the connection consumer gets errors such as communication link failures etc.. In order to avoid that, a validationQuery, an SQL statement specific to DBMS type, can be used which runs before using the connection. In WSO2 middleware platform, you usually use central governance/configuration registry to store SOA metadata and variou