Livesite components can consume DCRs for rendering, there is a DCR property that can allow you to inject one or multiple DCRs into your component xml. If you need a more custom mechanism for which dcrs need to be injected into a component you can using an external java implementation to inject what ever information you want into the component xml, including call outs to Databases. Livesite uses Data Deploy to transfer targeting information to the runtime environment. I recommend you see the Developers guide for additional information on component development.