/**
* Try to find a ResultColumn in the table represented by this FromBaseTable that matches the name
* in the given ColumnReference.
*
* @param columnReference The columnReference whose name we're looking for in the given table.
* @return A ResultColumn whose expression is the ColumnNode that matches the ColumnReference.
* Returns null if there is no match.
* @exception StandardException Thrown on error
*/
public ResultColumn getMatchingColumn(ColumnReference columnReference) throws StandardException {
ResultColumn resultColumn = null;
String columnsTableName;
/*
** RESOLVE: When we add support for schemas, check to see if
** the column name specifies a schema, and if so, if this
** table is in that schema.
*/
columnsTableName = columnReference.getTableName();
// post 681, 1 may be no longer needed. 5 is the default case
// now but what happens if the condition is false? Investigate.
if (columnReference.getGeneratedToReplaceAggregate()) // 1
{
resultColumn = resultColumns.getResultColumn(columnReference.getColumnName());
} else if (columnsTableName == null || columnsTableName.equals(correlationName)) // 5?
{
resultColumn =
resultColumns.getAtMostOneResultColumn(columnReference, correlationName, false);
}
if (resultColumn != null) {
columnReference.setTableNumber(tableNumber);
columnReference.setColumnNumber(resultColumn.getColumnPosition());
}
return resultColumn;
}
