Searching from structured data

In certain situations, we may want to find out whether a given document should be included or not; that is, a simple binary answer. On the other hand, there are other types of queries that are relevance-based. Such relevance-based queries also return a score against each document to say how well that document fits the query. Most structured queries do not need relevance-based scoring, and the answer is a simple yes/no for any item to be included or excluded from the result. These structured search queries are also referred to as term-level queries.

Let's understand the flow of a term-level query's execution:

Figure 3.2: Term-level query flow

As you can see, the figure is divided into two parts. The left-hand half of the figure depicts what happens at the time of indexing, and the right-hand half depicts what happens at the time of a query...