FQL

Flattening

By default FQL produces one table row per resource. But there are clear cases where you don't want that.

Rows for deeper values

To create a table from values deeper inside a resource, where it is not relevant for this specific result, to know to which resource the values belong, you can follow up with a for clause instead of starting with a select.

Compare this:

from StructureDefinition
select snapshot.element.constraint.human

This will result in one output row per StructureDefinition. While the following statement will put all the human readable constraints from all StructureDefinitions in one long table.

from StructureDefinition
for
    snapshot.element.constraint 
select
    human

Example output:

human
If the resource is contained in another resource, it SHALL NOT contain nested Resources
If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated
If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource

In some cases you want to display the array of a single resource as a table. For this purpose a top level for clause is also useful: the select field list will be grouped as one row with three columns for each page.

from ImplementationGuide
for page.page
select { 
    source,
    title,
    kind
}

Example output (top pages from this very Guide):