FireDAC Components for REST

Build 23.0.8804

Flattened Documents Model

For users who simply need access to the entirety of their data, flattening the data into a single table is the best option. The component will use streaming and only parses the data once per query in this mode.

Joining Object Arrays into a Single Table

With DataModel set to "FlattenedDocuments", the component returns a separate table for each object array, but implicitly JOINed to the parent table. Any nested sibling XPath values (child paths at the same height) will be treated as a SQL CROSS JOIN.


Below is a sample query and the results, based on the sample document in Raw Data and parsing based on the XPaths /root/people, /root/people/vehicles, and /root/people/vehicles/maintenance. This implicitly JOINs the people element with the vehicles element and implicitly JOINs the vehicles element with the maintenance element.

Connection String

Use the following connection string to query the Raw Data in this example.



The following query drills into the nested elements in each people element. Since the XPath property included the vehicles node, you can query an element of a vehicle explicitly.

  [personal.age] AS age,
  [personal.gender] AS gender,
  [] AS name_first,
  [] AS name_last,
  [] AS ins_company,
  [insurance.policy_num] AS ins_policy_num,
  [date] AS maint_date,
  [desc] AS maint_desc


With horizontal and vertical flattening based on the described paths, each vehicle element is implicitly JOINed to its parent people element and each maintenance element is implicitly JOINed to its parent vehicle element.

20MJohnDoeinternetcarHonda CivicABC Insurance123452017-07-17oil change
20MJohnDoeinternetcarHonda CivicABC Insurance123452018-01-03new tires
20MJohnDoeinternettruckDodge RamABC Insurance123452017-08-27new tires
20MJohnDoeinternettruckDodge RamABC Insurance123452018-01-08oil change
24FJaneRobertsphonecarToyota CamryCar Insurance987652017-05-11tires rotated
24FJaneRobertsphonecarToyota CamryCar Insurance987652017-11-03oil change
24FJaneRobertsphonecarHonda AccordCar Insurance987652017-10-07new air filter
24FJaneRobertsphonecarHonda AccordCar Insurance987652018-01-13new brakes

See Also

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Build 23.0.8804