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QuerySearch Metamodel

The QuerySearch can be modeled using the elements in the QuerySearch metamodel. To retain backwards compatibility, when adding the option enableQuerySearch to a DataElement, the expanders will implicitly create an instance of the QuerySearch element linked to that DataElement and has the name of the DataElement. This will generate the QuerySearch in mostly the same way as version 1.x did.

QuerySearch element​

The QuerySearch element is linked to a DataElement. This means that it is possible to create more than one QuerySearch implementation for a single DataElement.

Like DataElement, XML model files for QuerySearch elements are stored in a folder under the Component's model folder, with the name querySearchs. Similarly, the name of the QuerySearch will also be the name of the file.

Example

Let's say we wish to create a QuerySearch with name MyFirst, for the element Example in component examples, the file will be as follows:

Path: <sourceBase>/components/examples/model/querySearchs/MyFirst.xml

<querySearch name="MyFirst">
</querySearch>

This will generate files such as the QuerySearch class as <dataElement.packageName>.query.MyFirstQuerySearch and the QueryFilter as <dataElement.packageName>.query.MyFirstQueryFilter.

Option
useDefaultOrder QuerySearch

To avoid databases returning differently ordered results in between queries on the same dataset, this option will automatically append an ordering constraint that orders ascending on the id field. This functionality can be especially important when dealing with pagination of data.

<options>
  <useDefaultOrder/>
</options>

QueryFilterField element​

It is possible to model the fields in a QuerySearch's QueryFilter class. To this end there is a QueryFilterField element to model these fields. The types of these fields are defines as regular ValueTypes.

Fields are defined in the XML model file of the QuerySearch instance itself. The field types can be defined either in an expander bundle's data resources or directly under the component model in the queryFilterFieldTypes folder as its own file.

Example

In the following example two fields are added to the QuerySearch instance:

<querySearch name="MyFirst">
  <fields>
    <field name="name">
      <type name="String">
    </field>
    <field name="someReference">
      <type name="DataRef">
    </field>
  </fields>
</querySearch>