代码：
// Include the top-level Vertica SDK file
#include "/opt/vertica/sdk/include/Vertica.h"
#include <sstream>
#include <iostream>
using namespace Vertica;
using namespace std;
// Using the Vertica namespace means we don't have to prefix all
// class references with Vertica::
using namespace Vertica;
/*
* ScalarFunction implementation for a UDSF that adds
* two numbers together.
*/
class Add2Ints : public ScalarFunction
{
public:
/*
* This function does all of the actual processing for the UDF.
* In this case, it simply reads two integer values and returns
* their sum.
*
* The inputs are retrieved via arg_reader
* The outputs are returned via arg_writer
*/
virtual void processBlock(ServerInterface &srvInterface,
BlockReader &arg_reader,
BlockWriter &res_writer)
{
// While we have input to process
do
{
// Read the two integer input parameters by calling the
// BlockReader.getIntRef class function
const vint a = arg_reader.getIntRef(0);
const vint b = arg_reader.getIntRef(1);
// Call BlockWriter.setInt to store the output value, which is
// two input values added together
res_writer.setInt(a+b);
// Finish writing the row, and advance to the next output row
res_writer.next();
// Continue looping until there are no more input rows
}
while (arg_reader.next());
}
};
/*
* This class provides metadata about the ScalarFunction class, and
* also instantiates a member of that class when needed.
*/
class Add2IntsFactory : public ScalarFunctionFactory
{
// return an instance of Add2Ints to perform the actual addition.
virtual ScalarFunction *createScalarFunction(ServerInterface &interface)
{
// Calls the vt_createFuncObj to create the new Add2Ints class instance.
return vt_createFuncObj(interface.allocator, Add2Ints);
}
virtual void getPrototype(ServerInterface &interface,
ColumnTypes &argTypes,
ColumnTypes &returnType)
{
// Takes two ints as inputs, so add ints to the argTypes object
argTypes.addInt();
argTypes.addInt();
// returns a single int, so add a single int to the returnType object.
// Note that ScalarFunctions *always* return a single value.
returnType.addInt();
}
};
// Determine the length of the varchar string being returned.
virtual void Add2IntsFactory::getReturnType(ServerInterface &srvInterface,const SizedColumnTypes &argTypes,SizedColumnTypes &returnType)
{
const VerticaType &t = argTypes.getColumnType(0);
returnType.addVarchar(t.getVarcharLength());
}
// Register the factory with Vertica
RegisterFactory(Add2IntsFactory);
错误 ：
'::' 标记之前的预期初始化程序
能否请你帮忙？