Meta Query

Tips & examples

Invisible element that runs a data query and exposes data, loading, and error selectors for other elements on the page.

When to use

A page needs a query result no visible element already loads — e.g. a KPI count, a lookup, or an aggregate used by several expressions.
Two or more elements should share the same query result instead of each fetching it independently.
It is typically created under the hood by other templates when they need shared query data.

What you need

Points at a view/query via dataSource.queryName, optionally with a fixed filter expression and a response format. It renders nothing; failures only surface when another element reads its error selector.

Examples

Loading a single aggregate row to title a dashboard.

Avoid

Adding it when a visible element on the page already loads the same rows — read from that element instead.
Using it to fetch large result sets for display; use a Table/List for paging, sorting, and dense layouts.
Creating multiple meta queries when one shared query result could be read by several consumers.

Properties

Editor properties

Configure these in the Application Designer property panel. Group headings mirror the editor where possible. Data Source is where the element gets its rows or field binding (a view/query, a connector operation, or a parent form field). References appear only for view-backed sources and map foreign-key ID columns to readable labels from another view.

Data SourcerequiredSettings group: Where this element loads its data (view, query, connector, or element).
Default: {"queryName":""}
FilterrequiredCustom expression: Row filter applied when loading data.
Default: buildCustomExpressionValue("null")
Initial LoadrequiredYes / no: Configuration for initial Load.
Default: true
Load on ChangerequiredYes / no: Configuration for load On Change.
Default: true

Inside dataSource: (dataSource)

Query NamerequiredText

Named query or server query that supplies data.

Default: none

Response FormatoptionalOne of: json, geo, text, xml, bytea (or not set)

Configuration for response Format.

Choices

json
geo
text
xml
bytea

Default: none

Sizing

Default size when dropped on a page: 0 × 0.

Expressions

Values you can read in expressions

Other parts of your app can read live values from this element in custom expressions:

elements.todosQuery.<property>

loading boolean Indicates if the data is in process of being loaded from the server. elements.todosQuery.loading

When True while fetching. Guard anything that would otherwise show a wrong figure before the data arrives.

error string Error message when the last operation failed. elements.todosQuery.error

When The only way a failure surfaces — the element itself renders nothing, so expose this in a status component if the query can fail.

data Array<object> The data rows. elements.todosQuery.data

When The fetched rows (or shaped result). Every consumer reads it by expression (e.g. `elements.<id>.data`).

To use one of these, open the property you want to drive on the other element, switch it to expression mode in the Expression Editor, and enter:

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elements.todosQuery.data

Replace todosQuery with this element’s unique id. Select the element in Application Designer and copy the id chip at the top of the right-hand property panel.

Composition

Where you can place it

Internal element: not draggable by builders. It is created and configured automatically by other elements/templates that need data.

Sample configuration

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{
  "config": {
    "dataSource": {
      "queryName": "todos",
      "responseFormat": "json"
    },
    "filter": "@@expression:'value'",
    "initialLoad": false,
    "loadOnChange": false
  }
}