/// <summary>
/// Returns the hierarchical object type of a foreign key table relation
/// for up stream hierarchical properties.
/// </summary>
/// <remarks>
/// For example, UpToEmployeesByReportsTo has an object type of
/// Employees.
/// </remarks>
public string UpStreamObjectType(TableRelation tr)
{
if (tr.IsOneToOne && tr.IsDirect)
{
return this.Entity(tr.ForeignTable);
}
if (tr.IsManyToMany)
{
if (tr.ForeignTable.PrimaryKeys.Count == 2)
{
return this.Entity(tr.CrossReferenceTable);
}
}
if (tr.IsManyToOne)
{
return this.Entity(tr.ForeignTable);
}
return null;
}
/// <summary>
/// Returns the hierarchical object type of a foreign key table relation
/// for down stream hierarchical properties.
/// </summary>
/// <remarks>
/// For example, EmployeesColectionByReportsTo has an object type of
/// Employees.
/// </remarks>
public string DownStreamObjectType(TableRelation tr)
{
if (tr.IsOneToOne && !tr.IsDirect)
{
return this.Entity(tr.ForeignTable);
}
if (tr.IsZeroToMany)
{
return this.Entity(tr.ForeignTable);
}
return null;
}
/// <summary>
/// Returns the hierarchical object name of a foreign key table relation
/// for the up stream hierarchical property
/// </summary>
/// <remarks>
/// For example, UpToEmployeesByReportsTo.
/// </remarks>
public string UpStreamObjectName(TableRelation tr)
{
if (tr.IsOneToOne && tr.IsDirect)
{
return this.sUpToPrefix + this.EntityRelationName(tr.ForeignTable);
}
if (tr.IsManyToMany)
{
if (tr.ForeignTable.PrimaryKeys.Count == 2)
{
return this.sUpToPrefix + this.CollectionRelationName(tr.CrossReferenceTable, tr.ForeignTable);
}
}
if (tr.IsManyToOne)
{
return this.sUpToPrefix + this.EntityRelationName(tr.ForeignTable, tr.PrimaryColumns[0], tr.IsSelfReference);
}
return null;
}
/// <summary>
/// Returns the hierarchical object name of a foreign key table relation
/// for the down stream hierarchical property
/// </summary>
/// <remarks>
/// For example, EmployeesCollectionByReportsTo.
/// </remarks>
public string DownStreamObjectName(TableRelation tr)
{
if (tr.IsOneToOne && !tr.IsDirect)
{
return this.EntityRelationName(tr.ForeignTable);
}
if (tr.IsZeroToMany)
{
if (tr.IsSelfReference)
{
return this.CollectionRelationName(tr.ForeignTable, tr.PrimaryColumns[0], tr.IsSelfReference);
}
else
{
return this.CollectionRelationName(tr.ForeignTable, tr.ForeignColumns[0], tr.IsSelfReference);
}
}
return null;
}
/// <summary>
/// Returns true if the TableRelation for the foreign key
/// is down stream from current table.
/// </summary>
/// <remarks>
/// True for zero to many.
/// True for one side of a one to one, where
/// the foreign table is the one with the FK constraint defined.
/// </remarks>
public bool IsDownStream(TableRelation tr)
{
if (tr.IsOneToOne && !tr.IsDirect)
{
return true;
}
if (tr.IsZeroToMany)
{
return true;
}
return false;
}
/// <summary>
/// EXPERIMENTAL!
/// This creates an instance of the TableRelation Class
/// so that it can be accessed in templates using
/// Microsoft script (VBScript or JScript.)
/// </summary>
/// <remarks>
/// THIS IS EXPERIMENTAL!
/// As yet, it does not work for VBScript.
/// </remarks>
/// <example>
/// In JScript:
/// <code>
/// var tableRel = DnpUtils.CreateTableRelation(tableMeta, foreignKey);
/// </code>
/// In VBScript:
/// <code>
/// Dim tableRel
/// Set tableRel = DnpUtils.CreateTableRelation(tableMeta, foreignKey)
/// </code>
/// </example>
public TableRelation CreateTableRelation(ITable tableMeta, IForeignKey foreignKey)
{
TableRelation tr = new TableRelation(tableMeta, foreignKey);
return tr;
}
