90 likes | 221 Views
ECD Construction Example. From Weaver. Start off with…. The ERD (or extract of) the system. Delivery. Delivery Slot. Delivery Line. Purchase Order Line. Step one.
E N D
ECD Construction Example From Weaver
Start off with… • The ERD (or extract of) the system Delivery Delivery Slot Delivery Line Purchase Order Line
Step one • Identify all data entities which are effected by the event (in this case “Arrange Delivery”) – use the effects from the ELH and/or EEM. Also define the entry point (“Delivery”) Delivery Delivery Slot Delivery Line Purchase Order Line
Step two • Identify simultaneous effects for the event in question – i.e. effecting more than one occurrence of data entity in different ways . This would give rise to a separate box for each entity role. Stock [merged] Please note: This is a disjoint example taken from another LDM Stock [resulting]
Step three • Identify where an event affects a data entity in one or more mutually exclusive ways – add these effects as options under the data entity. These can be discerned from ELH roles listed in round brackets. Delivery o o Existing New
Step four • Identify data entities affected iteratively (i.e. repeatedly) by the event. Set of Delivery lines Set of Delivery slots Delivery * * o o Existing New Delivery line Delivery slot Purchase Order line
Step five • Identify one-to-one effects and connect with double-sided arrow lines. The question to ask for each entity is… For each affected occurrence of this entity, is there a directly related occurrence, or set of occurrences) in any of the other entities that is also affected by the event in question? Set of Delivery lines Delivery * o o Set of Delivery slots Delivery line Existing New * Delivery slot Purchase Order line
Step six • Add non-updated data entities (none in this example, but…) Set of Delivery lines Delivery * o o Set of Delivery slots Delivery line Existing New * Delivery slot Purchase Order line Product Imagine if we required product details One every delivery line (hypothetical)
Step seven (last step) • List the event data at the ECD entry point. Include entity key and any data fields required for update. Delivery ID Slot ID P.O. No. P.O. Line No. Quantity : : Delivery : : : :