internal override SelectableScheme GetSelectableSchemeFor(int column, int originalColumn, Table table)
{
// First check if the given SelectableScheme is in the column_scheme array
SelectableScheme scheme = columnScheme[column];
if (scheme != null)
{
if (table == this)
{
return(scheme);
}
return(scheme.GetSubsetScheme(table, originalColumn));
}
// If it isn't then we need to calculate it
SelectableScheme ss;
// Optimization: The table may be naturally ordered by a column. If it
// is we don't try to generate an ordered set.
if (sortedAgainstColumn != -1 &&
sortedAgainstColumn == column)
{
InsertSearch isop = new InsertSearch(this, column, CalculateRowReferenceList().Cast <int>());
isop.RecordUid = false;
ss = isop;
columnScheme[column] = ss;
if (table != this)
{
ss = ss.GetSubsetScheme(table, originalColumn);
}
}
else
{
// Otherwise we must generate the ordered set from the information in
// a parent index.
Table parentTable = referenceList[vtTableInfo.IndexOfTable(column)];
ss = parentTable.GetSelectableSchemeFor(vtTableInfo.AdjustColumnOffset(column), originalColumn, table);
if (table == this)
{
columnScheme[column] = ss;
}
}
return(ss);
}
/// <inheritdoc/>
public override DataObject GetValue(int column, long row)
{
int tableNum = JoinedTableInfo.IndexOfTable(column);
Table parentTable = ReferenceTables[tableNum];
if (row >= outerRowCount)
{
row = ReferenceRows[tableNum][(int)row - outerRowCount];
return(parentTable.GetValue(JoinedTableInfo.AdjustColumnOffset(column), row));
}
if (outerRows[tableNum] == null)
{
// Special case, handling outer entries (NULL)
return(new DataObject(TableInfo[column].DataType, null));
}
row = outerRows[tableNum][(int)row];
return(parentTable.GetValue(JoinedTableInfo.AdjustColumnOffset(column), row));
}