ent_link
- Last UpdatedNov 20, 2024
- 1 minute read
The ent_link table defines parent-child relationships between entities. In the physical entity hierarchy there is sometimes a need to have many-to-many relationships among the entities, e.g., defining many groups of lathes with different functionality, but allowing any particular lathe to be a member of >1 group, or defining groups to be production cells, reporting groups for comparison of like machines, maintenance responsibility groups, etc.
The table allows for many-to-many relationships between entities to be defined at any level. However, at first sight it appears that this would only occur between levels 3 and 4 in the SP95 model. When many-to-many relationships are defined there is no restriction on multiple parent entities being at the same level in the hierarchy.
Note that there is a record in this table for every parent-child relationship between entities, not just those where the child has multiple parents.
|
Field |
Datatype |
PK |
Nulls? |
Description |
|---|---|---|---|---|
|
parent_ent_id |
int32 |
Y |
N |
Identify parent entity |
|
child_ent_id |
int32 |
Y |
N |
Identify child entity |
|
last_edit_comment |
string254 |
N |
Y |
Reserved for internal use to indicate why this record was changed |
|
last_edit_by |
string40 |
N |
Y |
Who last changed this record |
|
last_edit_at |
tdatetime |
N |
N |
When this record was last changed |
|
row_id |
ID 1 |
N |
N |
Unique row identifier, for audit trail |
FK from parent_ent_id to ent. (Cascade delete implemented by SP)
FK from child_ent_id to ent. (Cascade delete implemented by SP)