MySQL C++ Connector: undefined reference to `get_driver_instance'
I've been trying to get the MySQL connector working I've installed both the connector and the mysql client library but I am still getting this error:
obj/Database.obj: In function `Database::connect()':
/home/xeross/alpine/src/server/Database.cpp:13: undefined reference to `get_driver_instance'
collect2: ld returned 1 exit status
make[2]: *** [alpine-server] Error 1
make[1]: *** [.build-conf] Error 2
make: *** [.build-impl] Error 2
Using Ubuntu 10.04 And my makefile is as follows:
INCLUDES = -I./src -I./src/shared
OUTDIR = bin
INTDIR = obj
OPTIONS = -ggdb -g3 -Wall -O0
alpine-server : Shared.a AsyncServerSocket.obj PlayerHandler.obj PacketHandler.obj Session.obj User.obj Database.obj init
g++ $(INCLUDES) $(OPTIONS) -static \
-pthread \
-lmysqlcppconn-static \
-o $(OUTDIR)/alpine-server src/server/main.cpp \
$(INTDIR)/AsyncServerSocket.obj \
$(INTDIR)/PacketHandler.obj \
$(INTDIR)/Database.obj \
$(INTDIR)/PlayerHandler.obj \
$(INTDIR)/Session.obj \
$(INTDIR)/User.obj \
$(INTDIR)/Shared.a \
-lboost_system \
-lmysqlclient
AsyncServerSocket.obj : src/server/AsyncServerSocket.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/AsyncServerSocket.obj src/server/AsyncServerSocket.cpp
PlayerHandler.obj : src/server/PlayerHandler.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/PlayerHandler.obj src/server/PlayerHandler.cpp
PacketHandler.obj : src/server/PacketHandler.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/PacketHandler.obj src/server/PacketHandler.cpp
Session.obj : src/server/Session.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/Session.obj src/server/Session.cpp
User.obj : src/server/User.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/User.obj src/server/User.cpp
Database.obj : src/server/Database.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/Database.obj src/server/Database.cpp
# Shared.a
Shared.a : Packet.obj Flags.obj AsyncSocket.obj Log.obj init
ar -cvq $(INTDIR)/Shared.a \
$(INTDIR)/Packet.obj \
$(INTDIR)/Flags.obj \
$(INTDIR)/AsyncSocket.obj \
$(INTDIR)/Log.obj
ranlib $(INTDIR)/Shared.a
Packet.obj : src/shared/packet.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/Packet.obj src/shared/packet.cpp
Flags.obj : src/shared/Flags.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/Flags.obj src/shared/Flags.cpp
AsyncSocket.obj : src/shared/AsyncSocket.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/AsyncSocket.obj src/shared/AsyncSocket.cpp
Log.obj : src/shared/Log.cpp init
g++ -c $(INCLUDES) $(OPTIONS) -o $(INTDIR)/Log.obj src/shared/Log.cpp
init:
mkdir -p bin obj
clean:
rm -f $(INTDIR)/*.obj $(INTDIR)/*.a
The Code
// Excerpt from .hpp file
#include <cppconn/driver.h>
#include <cppconn/connection.h>
#include <cppconn/resultset.h>
#include <cppconn/statement.h>
// End excerpt
void Database::connect()
{
std::stringstream connString;
connString << "tcp://";
connString << m_host;
connStri开发者_如何学Pythonng << ":";
connString << m_port;
m_driver = get_driver_instance(); // This guy is being a *****
m_conn = m_driver->connect(connString.str(), m_user, m_password);
m_conn->setSchema(m_database);
}
What can I do to fix this ?
Finally I could successfully compile a program with C++ connector in Ubuntu 10.10.
Initially I faced the same problem with "undefined reference to `get_driver_instance' " to solve this I declare my driver instance variable of MySQL_Driver type. For ready reference this type is defined in mysql_driver.h file. Here is the code snippet I used in my program.
sql::mysql::MySQL_Driver *driver;
try {
driver = sql::mysql::get_driver_instance();
}
and I compiled the program with -l mysqlcppconn linker option
Thank you so much, I got it fixed too. I had the exact experience.
I am using Eclipse CDT on 64 Bit CentOS and for anyone reading this here are the following steps .
- first, be sure that the following are in the code.
include "mysql_driver.h"
include "mysql_connection.h"
using namespace sql::mysql;
Be sure that in Eclipse you have specified in your Eclipse project settings. the
mysql/include
andmysql/include/cppconn
directories in your include and then also themysql/lib
in the library directory, then and more importantly you specify-lmysqlcppconn
.Be sure you got the -m64 set in the Eclipse compiler options too.
When you run your program, it may complain of missing
libmysqlcppconn.so.1
. Do this, copylibmysqlcppconn.so.1.0.5
in your/usr/lib64
directory. Make a link oflibmysqlcppconn.so.1
towardslibmysqlcppconn.so.1.0.5
within that directory.
Your program should now run.
You need to link with
-lmysqlcppconn -lmysqlcppconn-static
The first library contains the code for the headers in /usr/include/cppconn/, and the second library contains the code found in the headers mysql_driver.h and mysql_connection.h.
You'll need to add -lmysqlcppconn-static
after the object files that uses stuff inside that library.
The code would be more helpful than the make file but try adding using namespace sql;
to the top of Database.cpp.
// Excerpt from .hpp file
#include <cppconn/driver.h>
#include <cppconn/connection.h>
#include <cppconn/resultset.h>
#include <cppconn/statement.h>
using namespace sql; // <---- add here
To me was needed -lmysqlclient
g++ -o mariaS2json test.cpp -L/usr/lib/ -lmysqlcppconn -lmysqlclient
And now all works
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