Compile Error/Code Issue

[Freyja]

After about 2 years of sitting around dreading the idea of doing this on my
own, I finally decided to try to get my application functional again by
updating to the new code (with lack of C++ experience/much formal training
this is a daunting task).  After 6.5 hours of trial and error, research
galore and pure luck, I've managed to get a 'nearly' functional compile
going.  I seem to be stuck on a couple of errors which I'm sure are simple
and I'm just overlooking something.  If someone could lend me a hand and
point me in the right direction, or even tell me what I'm doing wrong, I
would greatly appreciate it.  I've included the errors and coresponding code
below.  Thank you!


######## Error 1 ########

DatabaseControl.cpp: In constructor 'DatabaseControl::DatabaseControl()':
DatabaseControl.cpp:45: error: returning a value from a constructor

####### Code 1 #########

DatabaseControl::DatabaseControl()
{

        // Connect to database server
        mysqlpp::Connection con(mysqlpp::use_exceptions);
        try {
                cout << "Connecting to database server..." << endl;
                con.connect(DBNAME, DBHOST, DBUSER, DBPASS);
        }
        catch (exception& er) {
                cerr << "Connection failed: " << er.what() << endl;
                return -1;
        }

######### Error 2 ########

DatabaseControl.cpp: In member function 'std::map<std::basic_string<char,
std::char_traits<char>, std::allocator<char> >, Command*,
std::less<std::basic_string<char, std::char_traits<char>,
std::allocator<char> > >, std::allocator<std::pair<const
std::basic_string<char, std::char_traits<char>, std::allocator<char> >,
Command*> > > DatabaseControl::getCommands()':
DatabaseControl.cpp:69: error: request for member 'query' in
'((DatabaseControl*)this)->DatabaseControl::con', which is of non-class type
'Connection*'

######## Code 2 ########

map<string, Command*> DatabaseControl::getCommands()
{
    map<string, Command*> theMap;

    try
    {
        mysqlpp::Query query = con.query();
        //Query query = con.query();
        //Query query = m_conDB->query();
        query << "SELECT * FROM tbl_commands";

        mysqlpp::Result res = query.store();
        //Result res = query.store();
        mysqlpp::Row row;
        //Row row;

        mysqlpp::Result::iterator it;
        //Result::iterator it;
        for(it = res.begin(); it != res.end(); ++it)
        {
            row = *it;
            Command *newCmd = new Command(
                        row["Name"].get_string(),
                        row["Code"].get_string(),
                        (int)row["MinPosition"],
                        (int)row["Level"],
                        (int)row["Logged"],
                        (int)row["Enabled"] );
            theMap[newCmd->getName()] = newCmd;
        }
    }
    catch(const mysqlpp::BadQuery& er)
    {
        cerr << "Error querying for Command:" << er.what() << endl;
    }

    return theMap;
}

########## Error 3 #########

DatabaseControl.cpp: In destructor 'virtual
DatabaseControl::~DatabaseControl()':
DatabaseControl.cpp:1270: warning: possible problem detected in invocation
of delete operator:
DatabaseControl.cpp:1270: warning: invalid use of undefined type 'struct
Connection'
DatabaseControl.h:18: warning: forward declaration of 'struct Connection'
DatabaseControl.cpp:1270: note: neither the destructor nor the
class-specific operator delete will be called, even if they are declared
when the class is defined.

######### Code 3 ##########

/**
 * Destructor for the class.  Disconnects from the database and
 * deletes the pointer to the database connection.
 */
DatabaseControl::~DatabaseControl()
{
        delete con;
        //delete m_conDB;
        con = NULL;
        //m_conDB = NULL;
}