FAQ
Q1. How can I make a column to refer to many other tables?
A1. You can assign it on attribute dialog box of table.
Note! In eXERD, during connecting relationship, if there exists
the same column name with the reference column added automatically,
eXERD asks whether you want to use that column. But if that column
refers to other table already, instead of reusing it, new reference
column is created to prevent mistakes.
Here is a simple example.
- In the relationship shown in the below diagram, you can
change 'main code' column refers to the parent tables in both sides,
instead of 'main code 2' column in 'bi-directional reference' table.
- After selecting bi-directional reference table, press Space and
open properties dialog box.
- Select code reference2 -> bi-directional reference
relationship in relationship(FK) items.
- Change child column to main
code from existing main code2.
- Now you can check that main code column of
bi-directional table refers to main code2 table.
- Now delete the needless main code2 column on bi-directional
table and finish the task.