You can select a value in an EQL result and use it to compose a follow-on query.
This enables users to interact with EQL results through a chart or a graph to compose follow-on queries. For example, when viewing a chart of year-to-date sales by country, a user might select a specific country for drill-down.
EQL is specifically designed to support this kind of follow-on query.
If, in the above example, the user selects the country United States, then the follow-on query should examine only sales of products in the United States. To filter to these items, a WHERE
clause like the following can be added:
WHERE DimGeography_CountryRegionName = 'United States'
For attributes with types other than string, a conversion is necessary to use the string representation of the value returned by EQL. For an integer attribute, such as DimDate_CalendarYear
, the string representation of the value must be converted to an integer for filtering, as follows:
WHERE DimDate_CalendarYear = TO_INTEGER('2006').
TO_BOOLEAN()
TO_DATETIME()
TO_DOUBLE()
TO_DURATION()
TO_GEOCODE()
TO_INTEGER()
TO_TIME()
Each of these accepts the string representation of values produced by the Dgraph. Note that no conversion is necessary for mdex:string
attributes.
To determine which conversion function to use, EQL results are accompanied by attribute metadata that describes the type of the attribute.