MCOL-1234 Nested CASE filters not processed

Change the way buildCaseFunction() handles the ptWorkStack and the rcWorkStack.

dbcon/execplan/arithmeticoperator.cpp

@@ -102,7 +102,7 @@ void ArithmeticOperator::unserialize(messageqcpp::ByteStream& b)
 
 bool ArithmeticOperator::operator==(const ArithmeticOperator& t) const
 {
-	if (fData == t.fData)
+	if (data() == t.data())
 		return true;
 	return false;
 }

dbcon/execplan/filter.cpp

@@ -72,7 +72,7 @@ const string Filter::toString() const
 
 bool Filter::operator==(const Filter& t) const
 {
-	if (fData == t.fData)
+	if (data() == t.data())
 		return true;
 	return false;
 }

dbcon/execplan/logicoperator.cpp

@@ -106,7 +106,7 @@ void LogicOperator::unserialize(messageqcpp::ByteStream& b)
 
 bool LogicOperator::operator==(const LogicOperator& t) const
 {
-	if (fData == t.fData)
+	if (data() == t.data())
 		return true;
 	return false;
 }

dbcon/execplan/predicateoperator.cpp

@@ -152,7 +152,7 @@ void PredicateOperator::unserialize(messageqcpp::ByteStream& b)
 
 bool PredicateOperator::operator==(const PredicateOperator& t) const
 {
-	if (fData == t.fData)
+	if (data() == t.data())
 		return true;
 	return false;
 }

dbcon/execplan/simplecolumn.cpp

@@ -370,16 +370,16 @@ bool SimpleColumn::operator==(const SimpleColumn& t) const
 		return false;
 	if (fColumnName != t.fColumnName)
 		return false;
-	if (fIndexName != t.fIndexName)
+//	if (fIndexName != t.fIndexName)
-		return false;
+//		return false;
 	if (fViewName != t.fViewName)
 		return false;
 	if (fOid != t.fOid)
 		return false;
-	if (fData != t.fData)
+	if (data() != t.data())
-		return false;
-	if (fAlias != t.fAlias)
 		return false;
+//	if (fAlias != t.fAlias)
+//		return false;
 	if (fTableAlias != t.fTableAlias)
 		return false;
 	if (fAsc != t.fAsc)

dbcon/execplan/treenodeimpl.cpp

@@ -63,7 +63,7 @@ const string TreeNodeImpl::toString() const
 
 bool TreeNodeImpl::operator==(const TreeNodeImpl& t) const
 {
-	if (fData == t.fData)
+	if (data() == t.data())
 		return true;
 	return false;
 }

dbcon/mysql/ha_calpont_execplan.cpp

@@ -3190,107 +3190,85 @@ FunctionColumn* buildCaseFunction(Item_func* item, gp_walk_info& gwi, bool& nonS
 		funcName = "case_searched";
 
 	funcParms.reserve(item->argument_count());
-	if (gwi.clauseType == SELECT || gwi.clauseType == HAVING || gwi.clauseType == GROUP_BY) // select clause
+	// so buildXXXcolumn function will not pop stack.
+    ClauseType realClauseType = gwi.clauseType;
+	gwi.clauseType = SELECT;
+
+	// We ought to be able to just build from the stack, and would 
+	// be able to if there were any way to know which stack had the 
+	// next case item. Unfortunately, parameters may have been pushed
+	// onto the ptWorkStack or rcWorkStack or neither, depending on type
+	// and position. We can't tell which at this point, so we
+	// rebuild the item from the arguments directly and then try to 
+	// figure what to pop, if anything, in order to sync the stacks.
+	for (int32_t i = item->argument_count()-1; i >=0; i--)
 	{
-		// the first argument
+		// For case_searched, we know the items for the WHEN clause will
-		if (funcName == "case_searched")
+		// not be ReturnedColumns. We do this separately just to save 
+		// some cpu cycles trying to build a ReturnedColumn as below.
+		// Every even numbered arg is a WHEN. In between are the THEN. 
+		// An odd number of args indicates an ELSE residing in the last spot.
+		if (funcName == "case_searched" &&
+			i % 2 == 0 && uint(i) != item->argument_count()-1)
 		{
-			for (uint32_t i = 0; i < item->argument_count(); i++)
+			sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
+			if (!gwi.ptWorkStack.empty() && *gwi.ptWorkStack.top()->data() == sptp->data())
 			{
-				if (i % 2 == 0 && i != 1 && i != item->argument_count()-1)
+				gwi.ptWorkStack.pop();
-				{
-					sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
-					funcParms.push_back(sptp);
-				}
-				else
-				{
-					ReturnedColumn* parm = buildReturnedColumn(item->arguments()[i], gwi, nonSupport);
-					if (parm)
-					{
-						sptp.reset(new ParseTree(parm));
-					}
-					else
-					{
-						sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
-					}
-					funcParms.push_back(sptp);
-				}
 			}
 		}
 		else
 		{
-			for (uint32_t i = 0; i < item->argument_count(); i++)
+			// First try building a ReturnedColumn. It may or may not succeed
+			// depending on the types involved. There's also little correlation 
+			// between buildReturnedColumn and the existance of the item on
+			// rwWorkStack or ptWorkStack.
+			// For example, simple predicates, such as 1=1 or 1=0, land in the
+			// ptWorkStack but other stuff might land in the rwWorkStack
+			ReturnedColumn* parm = buildReturnedColumn(item->arguments()[i], gwi, nonSupport);
+			if (parm)
 			{
-				ReturnedColumn* parm = buildReturnedColumn(item->arguments()[i], gwi, nonSupport);
+				sptp.reset(new ParseTree(parm));
-				if (parm)
+				// We need to pop whichever stack is holding it, if any.
+				if ((!gwi.rcWorkStack.empty()) && 
+					*gwi.rcWorkStack.top() == parm)
 				{
-					sptp.reset(new ParseTree(parm));
+					gwi.rcWorkStack.pop();
 				}
 				else
+				if (!gwi.ptWorkStack.empty())
 				{
-					sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
+					ReturnedColumn* ptrc = dynamic_cast<ReturnedColumn*>(gwi.ptWorkStack.top()->data());
-				}
+					if (ptrc && *ptrc == *parm)
-				funcParms.push_back(sptp);
-			}
-		}
-	}
-	else // where clause
-	{
-		// so buildXXXcolumn function will not pop stack.
-		gwi.clauseType = SELECT;
-		if (funcName == "case_searched")
-		{
-			for (int32_t i = item->argument_count()-1; i >=0; i--)
-			{
-				if (i % 2 == 0 && uint(i) != item->argument_count()-1)
-				{
-					// build item from arguments to avoid parm sequence complexity
-					sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
-					if (!gwi.ptWorkStack.empty())
 						gwi.ptWorkStack.pop();
 				}
-				else
-				{
-					ReturnedColumn* parm = buildReturnedColumn(item->arguments()[i], gwi, nonSupport);
-					if (parm)
-					{
-						sptp.reset(new ParseTree(parm));
-						if (!gwi.rcWorkStack.empty())
-							gwi.rcWorkStack.pop();
-					}
-					else
-					{
-						sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
-						if (!gwi.ptWorkStack.empty())
-							gwi.ptWorkStack.pop();
-					}
-				}
-				funcParms.insert(funcParms.begin(), sptp);
 			}
-		}
+			else
-		else // simple_case
-		{
-			for (uint32_t i = 0; i < item->argument_count(); i++)
 			{
-				ReturnedColumn* parm = buildReturnedColumn(item->arguments()[i], gwi, nonSupport);
+				sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
-				if (parm)
+				// We need to pop whichever stack is holding it, if any.
+				if ((!gwi.ptWorkStack.empty()) &&
+					*gwi.ptWorkStack.top()->data() == sptp->data())
 				{
-					sptp.reset(new ParseTree(parm));
+					gwi.ptWorkStack.pop();
-					if (!gwi.rcWorkStack.empty())
+				}
+				else
+				if (!gwi.rcWorkStack.empty())
+				{
+					// Probably won't happen, but it might have been on the
+					// rcWorkStack all along.
+					ReturnedColumn* ptrc = dynamic_cast<ReturnedColumn*>(sptp->data());
+					if (ptrc && *ptrc == *gwi.rcWorkStack.top())
+					{
 						gwi.rcWorkStack.pop();
+					}
 				}
-				else
-				{
-					sptp.reset(buildParseTree((Item_func*)(item->arguments()[i]), gwi, nonSupport));
-					if (!gwi.ptWorkStack.empty())
-						gwi.ptWorkStack.pop();
-				}
-				funcParms.push_back(sptp);
 			}
 		}
-		// recover clause type
+		funcParms.insert(funcParms.begin(), sptp);
-		gwi.clauseType = WHERE;
 	}
+	// recover clause type
+	gwi.clauseType = realClauseType;
 
 	if (gwi.fatalParseError)
 	{
@@ -4259,9 +4237,9 @@ void gp_walk(const Item *item, void *arg)
 				}
 				// bug 3137. If filter constant like 1=0, put it to ptWorkStack
 				// MariaDB bug 750. Breaks if compare is an argument to a function.
-				if ((int32_t)gwip->rcWorkStack.size() <=  (gwip->rcBookMarkStack.empty() ? 0 : gwip->rcBookMarkStack.top())
+//				if ((int32_t)gwip->rcWorkStack.size() <=  (gwip->rcBookMarkStack.empty() ? 0 : gwip->rcBookMarkStack.top())
-				&& isPredicateFunction(ifp, gwip))
+//				&& isPredicateFunction(ifp, gwip))
-//				if (isPredicateFunction(ifp, gwip))
+				if (isPredicateFunction(ifp, gwip))
 					gwip->ptWorkStack.push(new ParseTree(cc));
 				else
 					gwip->rcWorkStack.push(cc);
@@ -5505,7 +5483,9 @@ int getSelectPlan(gp_walk_info& gwi, SELECT_LEX& select_lex, SCSEP& csep, bool i
 						// @bug 1706
 						String funcStr;
 						ifp->print(&funcStr, QT_INFINIDB);
-						gwi.selectCols.push_back(string(funcStr.c_ptr()) + " `" + escapeBackTick(ifp->name) + "`");
+   					    string valStr;
+					    valStr.assign(funcStr.ptr(), funcStr.length());
+						gwi.selectCols.push_back(valStr + " `" + escapeBackTick(ifp->name) + "`");
 						// clear the error set by buildFunctionColumn
 						gwi.fatalParseError = false;
 						gwi.parseErrorText = "";