private void ReadTables(DataSchema dataSchema, IEnumIVMEModelElements elementEnumerator)
{
// Iterate over all the entities in the model, searching
// for tables.
// Each entity is a table, we gather column and index information from here
for (IVMEModelElement element = elementEnumerator.Next(); element != null; element = elementEnumerator.Next())
{
if (backgroundWorker.CancellationPending)
return;
if (element.Type == VMEModelElementKind.eVMEKindEREntity)
{
IVMEEntity entity = element as IVMEEntity;
Table newTable = new Table();
newTable.Name = entity.PhysicalName;
dataSchema.Tables.Add(newTable);
//
// Here we search for the columns of the table
//
IEnumIVMEAttributes columnEnumerator = entity.Attributes;
for (IVMEAttribute columnDefinition = columnEnumerator.Next(); columnDefinition != null; columnDefinition = columnEnumerator.Next())
{
if (backgroundWorker.CancellationPending)
return;
Column newColumn = new Column();
newColumn.Name = columnDefinition.PhysicalName;
string columnTypeName = GetColumnTypeName(columnDefinition.DataType);
newColumn.ColumnType = FindColumnType(dataSchema, columnTypeName);
if (newColumn.ColumnType == null)
{
throw CreateException("Column type " + columnTypeName + " used in table " + newTable.Name + " was not found in the type definition document");
}
newColumn.CanBeNull = columnDefinition.AllowNulls;
newTable.Columns.Add(newColumn);
}
//
// Now we search for indexes in the structure
//
IEnumIVMEEntityAnnotations indexesEnumerator = entity.EntityAnnotations;
for (IVMEEntityAnnotation indexDefinition = indexesEnumerator.Next(); indexDefinition != null; indexDefinition = indexesEnumerator.Next())
{
if (backgroundWorker.CancellationPending)
return;
bool isPrimaryKey = indexDefinition.kind == VMEEREntityAnnotationKind.eVMEEREntityAnnotationPrimary;
if (!isPrimaryKey)
{
// Primary keys in the Knightrunner DataSchema are not index objects
Index newIndex = new Index(newTable);
newIndex.Name = indexDefinition.PhysicalName;
newIndex.IsUnique = indexDefinition.kind == VMEEREntityAnnotationKind.eVMEEREntityAnnotationAlternate;
IEnumIVMEAttributes indexColumnEnumerator = indexDefinition.Attributes;
for (IVMEAttribute indexColumn = indexColumnEnumerator.Next(); indexColumn != null; indexColumn = indexColumnEnumerator.Next())
{
newIndex.Columns.Add(newTable.Columns[indexColumn.PhysicalName]);
}
newTable.Indices.Add(newIndex);
}
else
{
IEnumIVMEAttributes indexColumnEnumerator = indexDefinition.Attributes;
for (IVMEAttribute indexColumn = indexColumnEnumerator.Next(); indexColumn != null; indexColumn = indexColumnEnumerator.Next())
{
newTable.Columns[indexColumn.PhysicalName].InPrimaryKey = true;
}
}
}
}
}
}
private void ReadRelations(DataSchema dataSchema, IEnumIVMEModelElements elementEnumerator)
{
//
// Iterates over all the entities in the model, searching
// for relationships.
//
// for each relationship, we need to find the related tables
// and all the interesting properties of the relationship
//
for (IVMEModelElement element = elementEnumerator.Next(); element != null; element = elementEnumerator.Next())
{
if (element.Type == VMEModelElementKind.eVMEKindERRelationship)
{
IVMEBinaryRelationship relationship = element as IVMEBinaryRelationship;
if (relationship.FirstEntity != null && relationship.SecondEntity != null)
{
string relationName = relationship.PhysicalName;
Table primaryTable = dataSchema.Tables[relationship.FirstEntity.PhysicalName];
Table referencedTable = dataSchema.Tables[relationship.SecondEntity.PhysicalName];
//
// Now we need to add the columns that are used to mantain the
// relationship. We need two cursors, one for the primary
// table and the other for the referenced one
//
IEnumIVMEAttributes primaryColumnEnumerator = relationship.FirstAttributes;
IVMEAttribute primaryColumn = primaryColumnEnumerator.Next();
IEnumIVMEAttributes referencedColumnEnumerator = relationship.SecondAttributes;
IVMEAttribute referencedColumn = referencedColumnEnumerator.Next();
while (primaryColumn != null)
{
Column primaryDataColumn = primaryTable.Columns[primaryColumn.PhysicalName];
Column referencedDataColumn = referencedTable.Columns[referencedColumn.PhysicalName];
ForeignKey foreignKey = new ForeignKey();
foreignKey.FromTable = primaryTable;
foreignKey.ToTable = referencedTable;
foreignKey.Columns.Add(new ForeignKey.ColumnPair { FromColumn = primaryDataColumn, ToColumn = referencedDataColumn });
primaryColumn = primaryColumnEnumerator.Next();
referencedColumn = referencedColumnEnumerator.Next();
}
}
}
}
}
