Database Source

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If database is selected as the data source for a widget then the object or objects shown are retrieved directly from the database with a query. This data source is also supported in offline applications in which case the data will come from the database on the mobile device.

Components

See Search Bar.

Sort bar

See Sort Bar.

Properties

Entity (Path)

The entity (path) property specifies the target of the database query. A top-level data grid is always connected to an entity.

A nested data grid can either be connected to an entity or to an entity path starting in the entity of the containing data view. The entity path follows one association of type reference in the opposite direction in which the association’s arrow is pointing (from * to 1).

Please note that this differs from the association data source in that the objects are not retrieved from the client cache but directly from the database. The association is simply parsed as an extra constraint in the database query.

With this property you can influence if and when a search bar is shown.

Value Description
Never No search bar or search button are ever shown. Effectively disables search.
With button (initially open) The user can open and close the search bar using the search button; the search bar is initially open.
With button (initially closed) The user can open and close the search bar using the search button; the search bar is initially closed.
Always The search bar is always visible and cannot be close, nor is there a search button.

Default value: With button (initially closed)

If set to true, the grid will remain empty of contents until a search has been performed. This can be useful if the target entity contains an extremely large set of objects but most mutations only require a subset of the data. Waiting for search will ensure that no database query is performed until the desired subset is specified, thus skipping the initial loading period associated with major data retrievals.

Default value: false

Constraints

Constraints allow for custom, hard-coded limitations on the data displayed. This constraint will be applied after constraints already applied through security. Each constraint consists of an attribute, an operator and a value. Multiple constraints will limit the data even more (“and”). There is no way to create “or” constraints, except by switching to an XPath data source.

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