Searching Metadata Content
As you can see from the figure at the end of the previous section, queries against a Watson™ Explorer Engine search collection automatically search the title and snippet metadata content elements. However, attempting a content-specific search like year:1985 returns a message saying that no results were found. To correct this, we need to identify the fields that the Watson Explorer Engine application should handle as metadata fields that should be searched through the use of appropriately-phrased field:value queries.
Some metadata fields, like title, are configured for field-specific searches by default. For example, try the search title:stop. This demonstrates that the query is only being submitted against the contents of the title metadata field. (Compare the results of this search to the results for the general search for the word stop that you got four results for earler.
A form is the term used to describe the portion of a Watson Explorer Engine application that defines how to submit a query to an online resource (referred to as a source) in order to initiate the retrieval of results from that resource. For search collections, Watson Explorer Engine automatically creates two sources, each of which contains a form through which you can query that collection. One of these sources enables you to query the staging index, and the other enables you to query the live index. These automatically-created sources have the same name as the search collection that they are associated with, except that the source for querying the live index has the same name as your search collection, while the source created for querying the staging index has the string #staging appended to its name. For detailed information on the live versus the staging index, refer to the Search Collection Overview Panel section of the Watson Explorer Engine User Manual.
To identify metadata content elements that you can specifically reference in a query, you
must edit the form for the source used in that query. To do so, click the
List icon () to the right of the Sources entry in the Watson Explorer Engine administration tool's left-hand navigation bar and scroll
to binning-collection, or enter binning-collection in the Quick Jump field (the
quick jump field shows matching choices as you type), and click Select to
open that source, which is shown in Figure 1.

To proceed to the next section of this tutorial, click Adding Field Mappings.