In the PPDM data model,
only the columns defined as primary key are set to Not Null. All
other columns are set to null. This is the default. If
you have a business rule or implementation design decision that
states something like "all areas must have a coordinate
system", then you could change the Coord_System_Id column
in the AREA table to Not Null. This will impact all future
usage of the table because every row that is stored in that table
must have a value in that column. That is a big impact on the usage
of the table both in cleanup of existing data as well as
potentially altering applications to properly capture this
information when a row is created. It might be better to
create a batch job that finds any rows in the AREA table where the
Coord_System_Id column is null and email the owner (source) of the
row with a request to update this column.
If an implementing
company decides to set the PPDM_GUID value to ‘Not
Null’, there is a script available; as part of the 3.8
release, that will change the data model. There is also a
script that will put a unique index on each table as
well.
