Planning how to match entity instances

Matching entity instances is an important task in setting up your PolicyCenter implementation. When you create a new entity type or extend an existing type, you must consider which matching strategy to implement. You must also test your matcher implementation rigorously to confirm that you do not have the following types of matching errors:

• Matching two entity instances that actually refer to different items. This error causes PolicyCenter to discard a valid object.
• Not matching two entity instances that actually refer to the same item. This error causes PolicyCenter to create an invalid duplicate object.

Matching two objects is straightforward for transactions that are in sequence because you can rely on the ID and, for effective-dated objects, the FixedID properties. Transactions that occur out of sequence require careful consideration.