} // getTableFromItems()
public static List <FromItem> getTableFromItems(FromItem item)
{
List <FromItem> result = new List <FromItem>();
if (item.getTable() != null)
{
result.Add(item);
}
else if (item.getSubQuery() != null)
{
FromItem[] sqItems = getTableFromItems(item.getSubQuery());
for (int i = 0; i < sqItems.Length; i++)
{
result.Add(sqItems[i]);
}
}
else if (item.getJoin() != JoinType.None)
{
FromItem leftSide = item.getLeftSide();
result.AddRange(getTableFromItems(leftSide));
FromItem rightSide = item.getRightSide();
result.AddRange(getTableFromItems(rightSide));
}
else
{
throw new InvalidOperationException("FromItem was neither of Table type, SubQuery type or Join type: " + item);
}
return(result);
} // getTableFromItems()
private Column findColumnInAliasedTable(Column column, FromItem fromItem, String aliasPart, String columnPart)
{
if (column != null)
{
// ensure that if the column has already been found, return it
return(column);
}
Table table = fromItem.getTable();
if (table != null)
{
String alias = fromItem.getAlias();
if (alias != null && alias.Equals(aliasPart))
{
column = table.getColumnByName(columnPart);
}
}
else
{
FromItem leftSide = fromItem.getLeftSide();
column = findColumnInAliasedTable(column, leftSide, aliasPart, columnPart);
FromItem rightSide = fromItem.getRightSide();
column = findColumnInAliasedTable(column, rightSide, aliasPart, columnPart);
if (column != null)
{
Query subQuery = fromItem.getSubQuery();
if (subQuery != null)
{
List <FromItem> items = subQuery.getFromClause().getItems();
foreach (FromItem subQueryFromItem in items)
{
column = findColumnInAliasedTable(column, subQueryFromItem, aliasPart, columnPart);
}
}
}
}
return(column);
}
} // executePrimaryKeyLookupQuery()
protected DataSet materializeFromItem(FromItem fromItem, List <SelectItem> selectItems)
{
DataSet dataSet;
JoinType joinType = fromItem.getJoin();
if (fromItem.getTable() != null)
{
// We need to materialize a single table
Table table = fromItem.getTable();
List <SelectItem> selectItemsToMaterialize = new List <SelectItem>();
foreach (SelectItem selectItem in selectItems)
{
FromItem selectedFromItem = selectItem.getFromItem();
if (selectedFromItem != null)
{
if (selectedFromItem.equals(fromItem))
{
selectItemsToMaterialize.Add(selectItem.replaceFunction(null));
}
}
else
{
// the select item does not specify a specific
// from-item
Column selectedColumn = selectItem.getColumn();
if (selectedColumn != null)
{
// we assume that if the table matches, we will use the
// column
if (selectedColumn.getTable() != null && selectedColumn.getTable().Equals(table))
{
selectItemsToMaterialize.Add(selectItem.replaceFunction(null));
}
}
}
}
if (logger.isDebugEnabled())
{
logger.debug("calling materializeTable(" + table.getName() + "," + selectItemsToMaterialize + ",1,-1");
}
// Dispatching to the concrete subclass of
// QueryPostprocessDataContextStrategy
dataSet = materializeTable(table, selectItemsToMaterialize, 1, -1);
}
else if (joinType != JoinType.None)
{
// We need to (recursively) materialize a joined FromItem
if (fromItem.getLeftSide() == null || fromItem.getRightSide() == null)
{
throw new ArgumentException("Joined FromItem requires both left and right side: " + fromItem);
}
DataSet[] fromItemDataSets = new DataSet[2];
// materialize left side
List <SelectItem> leftOn = NArrays.AsList(fromItem.getLeftOn());
fromItemDataSets[0] = materializeFromItem(fromItem.getLeftSide(),
CollectionUtils.concat(true, selectItems, leftOn));
// materialize right side
List <SelectItem> rightOn = NArrays.AsList(fromItem.getRightOn());
fromItemDataSets[1] = materializeFromItem(fromItem.getRightSide(),
CollectionUtils.concat(true, selectItems, rightOn));
FilterItem[] onConditions = new FilterItem[leftOn.Count];
for (int i = 0; i < onConditions.Length; i++)
{
FilterItem whereItem = new FilterItem(leftOn[i], OperatorType.EQUALS_TO, rightOn[i]);
onConditions[i] = whereItem;
}
switch (joinType)
{
case JoinType.INNER:
dataSet = MetaModelHelper.getCarthesianProduct(fromItemDataSets, onConditions);
break;
case JoinType.LEFT:
dataSet = MetaModelHelper.getLeftJoin(fromItemDataSets[0], fromItemDataSets[1], onConditions);
break;
case JoinType.RIGHT:
dataSet = MetaModelHelper.getRightJoin(fromItemDataSets[0], fromItemDataSets[1], onConditions);
break;
default:
throw new ArgumentException("FromItem type not supported: " + fromItem);
}
}
else if (fromItem.getSubQuery() != null)
{
// We need to (recursively) materialize a subquery
dataSet = executeQuery(fromItem.getSubQuery());
}
else
{
throw new ArgumentException("FromItem type not supported: " + fromItem);
}
if (dataSet == null)
{
throw new ArgumentException("FromItem was not succesfully materialized: " + fromItem);
}
return(dataSet);
} // materializeFromItem()
