c++ build error, redefinition of static variable, undefined element

Question

I writing application using c++ and Qt. I have a problem with building application.

I get many error but everything refers to static variable and undefined function.

I don't redefine static in any place of my code.

lastid.h code:

#ifndef LASTID_H
#define LASTID_H

#include <iostream>
#include <stdio.h>
#include <vector>

using namespace std;

class LastId
{
private:
    static int customerLastId;
    static int itemLastId;
public:
    static void Init(vector<string> data)
    {
        customerLastId = atoi(data[0].c_str());
        itemLastId = atoi(data[1].c_str());
    }

    /**
     * Function incrementing lastid of customer
    */
    static void incrementCustomerLastId()
    {
        customerLastId++;
    }

    /**
     * Function incrementing lastid of item
    */
    static void incrementItemLastId()
    {
        itemLastId++;
    }
    /**
     * Function returning value of customer last id
    */
    static int getCustomerLastId()
    {
        return customerLastId;
    }

    /**
     * Function returning value of item last id
    */
    static int getItemLastId()
    {
        return itemLastId;
    }

};

int LastId::customerLastId = 0;
int LastId::itemLastId = 0;


#endif // LASTID_H

In class customer where i using it:

void Customer::init()
{
    LastId::incrementCustomerLastId();
    id = LastId::getCustomerLastId();
}

Second type of error is undefined function. Using the function getRecord i want to return object of type T with vector as a parameter of constructor. In each class with i use in this function i have a constructor with this format.

getRecord function:

template <typename T>
T Database::getRecord(string line)
{
    vector<string> conversion;
    int pos = 0;
    string temp;
    while ((pos = line.find(delimiter)) != string::npos) {
        temp = line.substr(0, pos);
        conversion.push_back(temp);
        line.erase(0, pos + 1);
    }
    conversion.push_back(line);
    T record(conversion);
    conversion.clear();
    conversion.shrink_to_fit();
    return record;
}

sample class constructor definition

Customer(vector<string> data);

sample calling code

    Database dbLoadCustomers("../data/customers.csv", 0);
    vector<Customer> customers = dbLoadCustomers.getRecords<Customer>();
    dbLoadCustomers.~Database();

Error list: error static redefinition

error undefined function