The OData Wizard makes it easy to select a subset of data in an OData data source. For example, we can easily create a table of all Employees which have a last name starting with a "D." From this we can select only the data we need like the employee's employee ID, their first and last names, and their hire date. Finally, we can sort the table by the date that the employee was hired.
This article will familiarize you with the main aspects of the wizard.
The OData Wizard Interface:
The wizard is composed of four sections: the Data pane, the "Middle" pane, the Returned Data pane, and the Query Statement pane.
The Data Pane
The Data Pane gives you a hierarchical view of your data structure, allowing you to quickly expand and scroll through the database.
- - An OData service.
- - Denotes a collection of entities in the service.
- - Represents a property of each entity in a collection.
- - Used to show links to other entity collections.
The Middle Pane
The middle pane has sections for: Resources, Filters, Selects, and OrderBy's. The Resources section allows you to specify collections of entities to work with. The Filters section is comprised of groups and filters. Groups allow you to specify filters, and the conditions under which the entity is returned (any of the filters true or all of the filters true). Filters are composed of:
- A Property of the entity which is analyzed.
- A Comparison Operation which is used to compare the property to a value. Some example operations include "equal to," "not equal to," and "starts with."
- A Value to Compare which may be a date, string, number or character. This value is compared to the specified property using the Comparison Operation.
The Select section simply specifies the properties which you would like to return from this query. If none are specified, then all properties of the entity are returned. Finally, the OrderBy section lets you select properties which determine the ordering of the returned results.
The Returned Data Pane
The Returned Data pane displays the data as it will be returned from the current query. It is updated as changes to the query are made.
The Query Statement Pane
The Query Statement pane displays the full OData query as it has been specified in the middle pane.