private void FindPaths()
{
Paths.Clear();
// Scan measures to find fact tables
List <Table> facts = new List <Table>();
foreach (IDataElement elem in this)
{
if (elem is MeasureDef)
{
facts.Add(((MeasureDef)elem).Source.Table);
}
}
if (facts.Count > 0)
{
// Uses fact tables as root nodes
TableTree tree = new TableTree();
foreach (Table fact in facts)
{
TableTreeNode n = new TableTreeNode(fact);
tree.Nodes.Add(n);
Walkthrough(n);
}
// Scan attributes to find dimension tables
List <Table> dimTables = new List <Table>();
foreach (IDataElement elem in this)
{
if (elem is AttributeDef)
{
AttributeDef attr = (AttributeDef)elem;
if (!dimTables.Contains(attr.KeyColumns[0].Table))
{
dimTables.Add(attr.KeyColumns[0].Table);
}
}
}
foreach (Table table in dimTables)
{
TableTreeNode n = tree.FindNodeByTable(table);
if (n != null)
{
JoinPath jp = n.GetJoinPath();
if (jp != null)
{
Paths.Add(jp);
}
}
}
}
}
private void Walkthrough(TableTreeNode node)
{
// Uses destination of all the relationsips of current table to build child nodes,
// keeps walkthrough till the end of the branch.
foreach (Relationship rel in node.Table.Relationships)
{
TableTreeNode child = new TableTreeNode(rel.Destination);
node.Add(child);
Walkthrough(child);
}
}
public JoinPath GetJoinPath()
{
List <Relationship> list = new List <Relationship>();
TableTreeNode current = this;
Table last = null;
// Trace back to root node which is a fact table and add all the paths(relationships) to the list
while (current != null)
{
TableTreeNode parent = current.Parent;
if (parent != null)
{
Relationship rel = parent.Table.FindRelationshipByDestination(current.Table);
if (rel != null)
{
list.Add(rel);
}
last = parent.Table;
}
current = parent;
}
return(new JoinPath(last, Table, list));
}
public TableTreeNode Add(TableTreeNode node)
{
node.Parent = this;
Children.Add(node);
return(node);
}