9 Nov
2015
9 Nov
'15
4:10 p.m.
Hi,
With Olivier, we are analyzing a big database schema (around 65 tables and 350 relations
between tables).
We try to reverse engineer the schema.
The visualization is not beautiful for several reasons :
1. the only way to position the tables in the visu is using the GridLayout. So there is a
spaghetti meal representation what is not easy to understand (please have a look at
DB_Schema_All_tables.png)
2. the idea is to linked the columns of two tables. Using RTArrowedLine, it is not
beautiful (see DB_Schema_with-arrows) since the attach points are only on South and North
Border of the shape whereas we would like to have them also on left and right.
3. Usually, in DB schema, the links between tables are orthogonal multi lines. But in
Roassal, the attach point are once again only on top or in bottom of the shape (see
DB_Schema_with_Multines).
4. Normally in database representations, the multi lines have arrows but since, in
Roassal, the direction of the arrow is computed from the start and end points of the line,
it looks ugly in case of multi line edge (see multiline arrows).
5. When a column in a table references another column of the same table, the edge is in
the middle of the table but we would like to have a recursive dependency represented as a
loop. Is it possible to do that with Roassal (recursive_dependency figure)?
Is there someone working on a real graph representation such as in graphviz where lines do
not cross or at minima and so the entities are grouped?
Can we easily add attached point? or define by default at least 4 attach points to box or
ellipse?
Is it possible to get multi lines with arrows but where the head of the arrow is computed
with the perpendicular of the last segment of the multi line edges?
Two more question that are not visible in these figures:
6. It seems that currently, it is not possible to play with the label font (size, italic,
bold…).
7. Is it possible to put a label near an extremity of an edge (such as a role in UML class
diagram)? And is it possible to put a label also in the middle of an edge to indicate the
name of an association?
Is it possible? If it is not the case, can you enhance Roassal to add these features?
Thanks in advance for your help.
Olivier and Anne
