Lesson 4: Hints and tips

Create an AFEnumerationSet

AFEnumerationSet bTypeEnum = database.EnumerationSets.Add("Building Type");
bTypeEnum.Add("Residential", 0);
bTypeEnum.Add("Business", 1);

Set AFAttributeTemplate properties

AFAttributeTemplate energyUsageAttrTemp =
meterBasicTemplate.AttributeTemplates.Add("Energy Usage");
energyUsageAttrTemp.Type = typeof(Single);
energyUsageAttrTemp.Categories.Add(tsDataA);
energyUsageAttrTemp.DefaultUOM = uom;
energyUsageAttrTemp.DataReferencePlugIn =
database.PISystem.DataReferencePlugIns["PI Point"];
energyUsageAttrTemp.ConfigString =
@"\\%@\Configuration|PIDataArchiveName%\%Element%.%Attribute%;UOM=kWh";

Set AFAttributeTemplate type to be an enumeration set

AFAttributeTemplate attrTemp = elemTemp.AttributeTemplates["Building Type"];
AFEnumerationSet enumSet = database.EnumerationSets["Building Type"];
attrTemp.TypeQualifier = enumSet;

Check in the changes

if (database.IsDirty)
database.CheckIn();

Commit changes using bulk CheckIn

In the exercise solution code, you perform CheckIn operations in bulk to improve performance. This is accomplished by calling CheckIn less frequently.

Tip: For most situations, avoid calling CheckIn on every object change because each causes a call to the SQL server. When making multiple modifications, a general rule of thumb is to check in 200 objects at a time. If more control is required over the list of objects to be checked in, use the CheckIn() method on a PISystem instance. See PISystem.Checkin Method.

Add Overloads

When adding AFElement objects to an AFElements collection, several Add methods are available. The methods can be roughly divided into two groups:

• Methods that accept a string denoting the new AFElement name and return a reference to the newly created AFElement.

  
  AFElement meters = database.Elements.Add("Meters");
  

• Methods that accept a reference to an existing AFElement object and return void

  A common use case for the second method is when adding an existing element as a weak reference to a parent element as in the following:

  AFReferenceType weakRefType = database.ReferenceTypes["Weak Reference"];
  AFElement meters = database.Elements["Meters"];
  AFElement buildingA = database.Elements["Meter Company"].Elements["Building A"];
  buildingA.Elements.Add(meters.Elements["Meter001"], weakRefType);