Using variables in topology

One of the most common use cases for this capability is to allow a developer to build an application that can dynamically connect to a source or target system in order to repeat a uniform series of activities against each system. For example, perhaps there is a requirement to connect to a thousand different servers in order to collect daily activity. Obviously it would not be practical to create a thousand physical data servers within the topology along with a thousand contexts, so instead we can create one data server and use a variable within it to direct subsequent activities towards each individual data server. In this recipe, we will examine the use of variables within the ODI topology.

Note

A very important point to remember is that since ODI establishes all physical connections at session start-up time, embedded topology variables must be resolved before the connections are opened. Therefore, any application using this technique must be "launched" from an...