the begginning

utils/funcexp/func_elt.cpp

@@ -0,0 +1,103 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+
+/****************************************************************************
+* $Id: func_elt.cpp 2665 2011-06-01 20:42:52Z rdempsey $
+*
+*
+****************************************************************************/
+
+#include <cstdlib>
+#include <string>
+using namespace std;
+
+#include "functor_str.h"
+#include "funchelpers.h"
+#include "functioncolumn.h"
+#include "rowgroup.h"
+using namespace execplan;
+
+#include "dataconvert.h"
+using namespace dataconvert;
+
+namespace funcexp
+{
+
+CalpontSystemCatalog::ColType Func_elt::operationType( FunctionParm& fp, CalpontSystemCatalog::ColType& resultType )
+{
+	return resultType;
+}
+
+string Func_elt::getStrVal(rowgroup::Row& row,
+							FunctionParm& parm,
+							bool& isNull,
+							CalpontSystemCatalog::ColType&)
+{
+	uint64_t number = 0;
+
+	//get number
+	switch (parm[0]->data()->resultType().colDataType)
+	{
+		case CalpontSystemCatalog::BIGINT:
+		case CalpontSystemCatalog::MEDINT:
+		case CalpontSystemCatalog::SMALLINT:
+		case CalpontSystemCatalog::TINYINT:
+		case CalpontSystemCatalog::INT:
+		case CalpontSystemCatalog::DOUBLE:
+		case CalpontSystemCatalog::FLOAT:
+		case CalpontSystemCatalog::CHAR:
+		case CalpontSystemCatalog::VARCHAR:
+		{
+			double value = parm[0]->data()->getDoubleVal(row, isNull);
+			number = (int64_t) value;
+			break;
+		}
+		case CalpontSystemCatalog::DECIMAL:
+		{
+			IDB_Decimal d = parm[0]->data()->getDecimalVal(row, isNull);
+			number = d.value / helpers::power(d.scale);
+			int lefto = (d.value - number * helpers::power(d.scale)) / helpers::power(d.scale-1);
+			if ( number >= 0 && lefto > 4 )
+				number++;
+			if ( number < 0 && lefto < -4 )
+				number--;
+			break;
+		}
+		default:
+			isNull = true;
+			return "";
+	}
+
+	if (number < 1)
+	{
+		isNull = true;
+		return "";
+	}
+
+	if (number > parm.size()-1 )
+	{
+		isNull = true;
+		return "";
+	}
+
+	return stringValue(parm[number], row, isNull);
+
+}
+
+
+} // namespace funcexp
+// vim:ts=4 sw=4: