/// <exception cref="System.IO.IOException"></exception>
protected internal Index(ByteBuffer tableBuffer, IList <IndexData> indexDatas, JetFormat
format)
{
ByteUtil.Forward(tableBuffer, format.SKIP_BEFORE_INDEX_SLOT);
//Forward past Unknown
_indexNumber = tableBuffer.GetInt();
int indexDataNumber = tableBuffer.GetInt();
// read foreign key reference info
byte relIndexType = tableBuffer.Get();
int relIndexNumber = tableBuffer.GetInt();
int relTablePageNumber = tableBuffer.GetInt();
byte cascadeUpdatesFlag = tableBuffer.Get();
byte cascadeDeletesFlag = tableBuffer.Get();
_indexType = tableBuffer.Get();
if ((_indexType == FOREIGN_KEY_INDEX_TYPE) && (relIndexNumber != INVALID_INDEX_NUMBER
))
{
_reference = new Index.ForeignKeyReference(relIndexType, relIndexNumber, relTablePageNumber
, (cascadeUpdatesFlag == CASCADE_UPDATES_FLAG), (cascadeDeletesFlag == CASCADE_DELETES_FLAG
));
}
else
{
_reference = null;
}
ByteUtil.Forward(tableBuffer, format.SKIP_AFTER_INDEX_SLOT);
//Skip past Unknown
_data = indexDatas[indexDataNumber];
_data.AddIndex(this);
}
/// <returns>
/// the Index referenced by this Index's ForeignKeyReference (if it
/// has one), otherwise
/// <code>null</code>
/// .
/// </returns>
/// <exception cref="System.IO.IOException"></exception>
public virtual HealthMarketScience.Jackcess.Index GetReferencedIndex()
{
if (_reference == null)
{
return(null);
}
Table refTable = GetTable().GetDatabase().GetTable(_reference.GetOtherTablePageNumber
());
if (refTable == null)
{
throw new IOException("Reference to missing table " + _reference.GetOtherTablePageNumber
());
}
HealthMarketScience.Jackcess.Index refIndex = null;
int idxNumber = _reference.GetOtherIndexNumber();
foreach (HealthMarketScience.Jackcess.Index idx in refTable.GetIndexes())
{
if (idx.GetIndexNumber() == idxNumber)
{
refIndex = idx;
break;
}
}
if (refIndex == null)
{
throw new IOException("Reference to missing index " + idxNumber + " on table " +
refTable.GetName());
}
// finally verify that we found the expected index (should reference this
// index)
Index.ForeignKeyReference otherRef = refIndex.GetReference();
if ((otherRef == null) || (otherRef.GetOtherTablePageNumber() != GetTable().GetTableDefPageNumber
()) || (otherRef.GetOtherIndexNumber() != _indexNumber))
{
throw new IOException("Found unexpected index " + refIndex.GetName() + " on table "
+ refTable.GetName() + " with reference " + otherRef);
}
return(refIndex);
}
