the begginning

dbcon/execplan/windowfunctioncolumn.h

@@ -0,0 +1,265 @@
+/* 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: windowfunctioncolumn.h 9679 2013-07-11 22:32:03Z zzhu $
+*
+*
+***********************************************************************/
+
+/** @file */
+
+#ifndef WINDOW_FUNCTION_COLUMN_H
+#define WINDOW_FUNCTION_COLUMN_H
+#include <string>
+#include <iosfwd>
+#include <vector>
+
+#include "returnedcolumn.h"
+#include "functor.h"
+
+namespace messageqcpp {
+class ByteStream;
+}
+
+/**
+ * Namespace
+ */
+namespace execplan { 
+
+// This enum is made consistant with mysql item_func_window
+enum WF_FRAME
+{
+	WF_PRECEDING = 0,
+	WF_FOLLOWING,
+	WF_UNBOUNDED_PRECEDING,
+	WF_UNBOUNDED_FOLLOWING,
+	WF_CURRENT_ROW,
+	WF_UNKNOWN
+};
+
+struct WF_Boundary
+{
+	WF_Boundary() {}
+	WF_Boundary(WF_FRAME frame):fFrame(frame) {}
+	~WF_Boundary() {}
+	const std::string toString() const;
+	void serialize(messageqcpp::ByteStream&) const;
+	void unserialize(messageqcpp::ByteStream&);
+	SRCP fVal;  /// has to evaluate to unsigned value
+	SRCP fBound; /// order by col +, -, date_add or date_sub for RANGE window
+	enum WF_FRAME fFrame;
+};
+
+struct WF_Frame
+{
+	WF_Frame(): fIsRange(true)
+	{
+		fStart.fFrame = WF_UNBOUNDED_PRECEDING;
+		fEnd.fFrame = WF_UNBOUNDED_FOLLOWING;
+	}
+	~WF_Frame() {}
+	const std::string toString() const;
+	void serialize(messageqcpp::ByteStream&) const;
+	void unserialize(messageqcpp::ByteStream&);
+	WF_Boundary fStart;
+	WF_Boundary fEnd;
+	bool fIsRange; /// RANGE or ROWS
+};
+
+/**
+ * @brief A class to represent the order by clause of window function
+ */
+struct WF_OrderBy
+{
+	WF_OrderBy() {}
+	WF_OrderBy(std::vector<SRCP> orders): fOrders(orders) {}
+	~WF_OrderBy() {};
+	const std::string toString() const;
+	void serialize(messageqcpp::ByteStream&) const;
+	void unserialize(messageqcpp::ByteStream&);
+	std::vector<SRCP> fOrders;
+	WF_Frame fFrame;
+};
+
+/**
+ * @brief A class to represent a functional column
+ * 
+ * This class is a specialization of class ReturnedColumn that
+ * handles a window function.
+ */
+class WindowFunctionColumn : public ReturnedColumn {
+
+public:
+	WindowFunctionColumn();
+	WindowFunctionColumn(const std::string& functionName, const uint32_t sessionID = 0);
+	WindowFunctionColumn(const WindowFunctionColumn& rhs, const uint32_t sessionID = 0);
+	virtual ~WindowFunctionColumn() {}
+	
+	/** get function name */
+	inline const std::string& functionName() const
+	{
+		return fFunctionName;
+	}
+	
+	/** set function name */
+	inline void functionName(const std::string functionName)
+	{
+		fFunctionName = functionName;
+	}
+	
+	/** get function parameters */
+	inline const std::vector<SRCP>& functionParms() const
+	{
+		return fFunctionParms;
+	}
+	
+	/** set function parameters*/
+	inline void functionParms(const std::vector<SRCP>& functionParms)
+	{
+		fFunctionParms = functionParms;
+	}
+	
+	/** get partition columns */
+	inline const std::vector<SRCP>& partitions() const
+	{
+		return fPartitions;
+	}
+	
+	/** set partition columns */
+	inline void partitions(const std::vector<SRCP>& partitions)
+	{
+		fPartitions = partitions;
+	}
+	
+	/** get order by clause */
+	inline const WF_OrderBy& orderBy() const
+	{
+		return fOrderBy;
+	}
+	
+	/** set order by clause */
+	inline void orderBy(const WF_OrderBy& orderBy)
+	{
+		fOrderBy = orderBy;
+	}
+	
+	/** make a clone of this window function */	
+	inline virtual WindowFunctionColumn* clone() const
+	{
+		return new WindowFunctionColumn (*this);
+	}
+	
+	std::vector<SRCP> getColumnList() const;
+	
+	/** output the function for debug purpose */
+	const std::string toString() const;
+		
+	/**
+	 * The serialization interface
+	 */
+	virtual void serialize(messageqcpp::ByteStream&) const;
+	virtual void unserialize(messageqcpp::ByteStream&);
+		
+	// util function for connector to use. 
+	void addToPartition(std::vector<SRCP>& groupByList);
+
+	virtual bool hasAggregate() {return false;}
+	virtual bool hasWindowFunc();
+	void adjustResultType();
+
+private:
+	/**
+	 * Fields
+	 */
+	std::string fFunctionName;					/// function name
+	std::vector<SRCP> fFunctionParms;		/// function arguments
+	std::vector<SRCP> fPartitions;			/// partition by clause
+	WF_OrderBy fOrderBy;								/// order by clause
+	
+	// not support for window functions for now.
+	virtual bool operator==(const TreeNode* t) const { return false; }
+	bool operator==(const WindowFunctionColumn& t) const;
+	virtual bool operator!=(const TreeNode* t) const { return false; }
+	bool operator!=(const WindowFunctionColumn& t) const;
+	
+	/***********************************************************
+	 *                 F&E framework                           *
+	 ***********************************************************/
+public:
+	virtual const std::string& getStrVal(rowgroup::Row& row, bool& isNull) 
+	{ 
+		evaluate(row, isNull);
+		return TreeNode::getStrVal(); 
+	}
+	
+	virtual int64_t getIntVal(rowgroup::Row& row, bool& isNull) 
+	{ 
+		evaluate(row, isNull);
+		return TreeNode::getIntVal(); 
+	}
+
+	virtual uint64_t getUintVal(rowgroup::Row& row, bool& isNull) 
+	{ 
+		evaluate(row, isNull);
+		return TreeNode::getUintVal(); 
+	}
+
+	virtual float getFloatVal(rowgroup::Row& row, bool& isNull)
+	{
+		evaluate(row, isNull);
+		return TreeNode::getFloatVal();
+	}
+	
+	virtual double getDoubleVal(rowgroup::Row& row, bool& isNull) 
+	{
+		evaluate(row, isNull);
+		return TreeNode::getDoubleVal(); 
+	}
+	
+	virtual IDB_Decimal getDecimalVal(rowgroup::Row& row, bool& isNull)
+	{
+		evaluate(row, isNull);
+		return TreeNode::getDecimalVal();
+	}
+	virtual int32_t getDateIntVal(rowgroup::Row& row, bool& isNull)
+	{
+		evaluate(row, isNull);
+		return TreeNode::getDateIntVal();
+	}
+	virtual int64_t getDatetimeIntVal(rowgroup::Row& row, bool& isNull)
+	{
+		evaluate(row, isNull);
+		return TreeNode::getDatetimeIntVal();
+	}
+	
+private:
+	void evaluate(rowgroup::Row& row, bool& isNull);
+};
+
+/**
+* ostream operator
+*/
+std::ostream& operator<<(std::ostream& output, const WindowFunctionColumn& rhs);
+
+/**
+ * utility function to extract all window function columns from a parse tree
+ */
+void getWindowFunctionCols(ParseTree* n, void* obj);
+
+} 
+#endif //WINDOW_FUNCTION_COLUMN_H