Selective Data In Form Display

On the data sources section of the form ladder, under the data source, change the init method to select the data you require.

public void init()

{

    QueryBuildRange qryBuildRange;

    super();

    qryBuildRange = this.query().dataSourceName(this.name()).addRange(fieldNum(Addresses,AddressType));

    qryBuildRange.value(queryValue('D'));

    qryBuildRange = this.query().dataSourceName(this.name()).addRange(fieldNum(Addresses,dateCommited));

    qryBuildRange.value(queryValue(dateNull()));

    qryBuildRange.status(RangeStatus::Hidden);

}

The .Status being set to RangeStatus::Hidden stops the user over-ruling the selection manually.