The sample service used is the TripPin service which simulates the service of an open trip management system. Our friend, Russell Whyte, who has formerly registered TripPin, would like to find out who are the other people in it. Want to contribute code snippet for another platform or suggest changes to this content? You can edit and submit changes to "Understanding OData in 6 steps" on its Github repository. REST principles also say, that every resource is identified by a unique identifier.
OData also enables defining key properties of a resource and retrieving it using the keys. In this step, Russell wants to find the information about himself by specifying his username as the key. For that, OData defines a series of system query options that can help you construct complicated queries for the resources you want.
With the help of that, our friend Russell can find out the first 2 persons in the system who have registered at least one trip that costs more than , and only display their first name and last name. REST principles require the using of simple and uniform interfaces. With that regard, OData clients can expect unified interfaces of the resources.
After having gone through the first 3 steps, Russell thinks the system is useful. He wants to add his best friend Lewis to the system. He finds out that all he needs to do is to send a POST request containing a JSON representation of Lewis' information to the same interface from which he requested the people information.
For that, the concept of relationships in OData can be defined among resources to add flexibility and richness to the data model. For example, in the TripPin OData service, people are related to the trips that they've booked using the system. Knowing that, Russell would like to invite Lewis to his existing trip in the U. For that purpose, OData supports defining functions and actions to represent such operations.
They are also resources themselves and can be bound to existing resources. If you have multiple tables that have a direct relationship to one or more of the already selected tables, you can select the Select Related Tables button. When you do, all tables that have a direct relationship to one or more of the already selected tables will be imported as well.
If this is the first time you're connecting using the OData Feed, select the authentication kind and enter your credentials if necessary. Then select Next. From the Navigator dialog, you can select a table, then transform the data in the Power Query Editor by selecting Transform Data. See this article for more information. Due to the architecture of OData and other web connectors, joins can be non-performant.
While you have the option to use navigation columns when merging between tables from an OData source, you don't have this option when merging with non-Odata sources. If you are seeing performance issues when merging an OData source, you should apply Table. Buffer to your OData query in the Advanced Editor, before you merge the data. In cases where you're passing in a URL to the OData connector that's not just the service root, for example, if you have a filter on the URL, when you set up refresh in the service you should select Skip Test Connection.
However, this won't work in most cases. Please choose another credential type. Entries can be part of a hierarchy and can also have related entries and related feeds through links. In order to find the shape of an OData Service along with its structure, known links and service operations, OData services also expose a Service Metadata Document.
Another key aspect of the model is an OData metadata document. They describe the Entity Data Model EDM for a given service, which is the underlying abstract data model used by OData services to formalize the description of the resources it exposes.
OData, originally started by Microsoft in , began to grow until the Microsoft team realized that for the standard to be fully embraced, it would need to move to Open Group Open Standards Organization. Following this move, Microsoft approached our team at Progress DataDirect known as the Switzerland of data access to cosign the project. We believe in a future of open standards and writing them in such a way as to apply to as many data sources as possible.
We care about standards like OData, JDBC and ODBC and take part in their development and innovation because this is how we make the highest quality data connectivity products in the industry. The OData standard is powerful. From producers to consumers, it offers tremendous benefits.
Knowing this, what are your next steps? How do you expose your data as OData or consume it? This solution is incredibly flexible and is hosted on your own servers.
You can learn more about Hybrid Data Pipeline in the video below—and don't forget to register to watch our on-demand webinar on the topic too. Technology researcher, thought leader and speaker working to enable enterprises to rapidly adopt new technologies that are adaptive, connected and cognitive. Subscribe to get all the news, info and tutorials you need to build better business apps and sites.
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