RelationLevelDef component

Obtained from the hierarchy palette, this component defines a query that returns data for all objects that are related to the level immediately above it. Typically, the relationship is a child relationship (n:child).

In Niagara 4.3 and later, the Inbound Relation Id and Outbound Relation Id properties on a relation level definition replace the “RelationId” and “Inbound” properties present in prior releases. Note that during station start-up, if the existing bog file contains a RelationId value, this value is copied to either an Inbound Relation Id or an Outbound Relation Id based on the inbound flag value.

Additionally, there is added support for multiple relation IDs on a single relation level definition. You may add multiple Inbound or Outbound Relation Ids separated by a comma. The results for any of these relation IDs display in the hierarchy. Note that only a single LevelElem will be added for each distinct Entity related by the specified Ids, even if the Entity is related multiple ways (any duplicate relation levels will be removed).

RelationLevelDef properties

Property	Value	Description
`Query Context`	Config Facets dialog box	The current location is one item that could be placed in the query context. The facet value is compared with the value of the context tag on a device or point at a lower level in the navigation tree. The query context can hold anything to be used in LevelDef queries. It is comparable to a hierarchy scoped variable. You could create multiple copies of such a hierarchy definition and then customize each copy with the query context of the specific hierarchy.
`Inbound Relation Ids`	Comma separated list of relationIds	Queries for inbound relations with the specified Ids. Any duplicate relation levels will be removed.
`Outbound Relation Ids`	Comma separated list of relationIds	Queries for outbound relations with the specified Ids. Any duplicate relation levels will be removed.
`Repeat Relation`	true, false (default)	When true, the specified relations are traversed until there are no further results. For example, if the relation ID “n:child” is specified, the relation level def would be repeatedly evaluated until an Entity is reached that has no children. When false, the relations level def will only be evaluated once.
`Sort`	`None`, `Ascending` (default), `Descending`	Determines the order in which results display.

RelationLevelDef component

RelationLevelDef properties

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