capture social media stream into mysql

An http stream of social media events has to be captured an persisted in a relational database (MySQL). The stream is similar in nature with YQL queries on Twitter, Facebook and Digg. Provisions have to be made for guaranteeing stream completeness and consistency. It is desired that the app will make differential queries (e.g. following Twitter recommendationsto retrieve only new tweets, others then those already persisted) Would be nice if a generic model/ architecture will be provided, such as social media streams could be captured from various sources. The app could be written on Java, PHP, Python, Ruby or any other reasonable programming language, such as it will be easy to deploy and maintain on a Linux virtual (cloud) machine. It would be nice if app will provide a simple way to customize the requests (such as ability to change keywords to be searched on).