Searching Workflows with Hierarchical Views

Workflows are prevalent in diverse applications, which can be scientific experiments, business processes, web services, or recipes. With the dramatically growing number of workflows, there is an increasing need for people to search a workflow repository using keywords and to retrieve the relevant ones. A workflow hierarchy is a three dimensional object containing multiple abstraction views of different granularity on the same workflow. This unique structure poses a new set of challenges compared to keyword search on tree or graph structures typically found in relational or XML data. In this paper, we define an informative, self-contained and concise search result on workflows to be a projection of a workflow hierarchy on a two dimensional viewing plane inferred from user queries. We then design and develop an efficient keyword search engine for workflows. Experimental evaluation demonstrates the effectiveness of our approach.