ECD Construction Example

1
ECD Construction Example

• From Weaver

2
Start off with

• The ERD (or extract of) the system

Delivery
Delivery Slot
Delivery Line
Purchase Order Line
3
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
4
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
5
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
6
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
7
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?

Delivery
Set of Delivery lines
o
o

Existing
New
Delivery line
Set of Delivery slots

Delivery slot
Purchase Order line
8
Step six

• Add non-updated data entities (none in this
  example, but)

Delivery
Set of Delivery lines

o
o
Existing
New
Delivery line
Set of Delivery slots

Delivery slot
Purchase Order line
Product
Imagine if we required product details One every
delivery line (hypothetical)
9
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