Variations of this question has been asked many times before, but I've searched through everything I can find on the web and still don't have a valid answer, or at least one that works.
I am trying to setup Code::Blocks to use MySql Connector in order to get the tutorial posted here to run. I have done everything to the best of my knowledge but still get an 'undefined reference' error on compile. I'm fairly certain it is a linking error.
obj\Release\main.o:main.cpp:(.text.startup+0x15e)
undefined reference to _imp__get_driver_instance' error: ld returned 1 exit status
OS: Windows 7 64bit
IDE: Code::Blocks 16.01
Settings->Compiler->Search Directories->Compiler:
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\include
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\include\cppconn
C:\local\boost_1_61_0
Settings->Compiler->Search Directories->Linker:
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\lib\opt
Settings->Compiler->Linker Settings->Link Libraries:
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\lib\opt\mysqlcppconn.lib
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\lib\opt\mysqlcppconn-static.lib
Like I said, there are lots of questions around the web about this particular error, but I haven't found anything with a solution for my setup. I admit I'm a little rusty on linking libraries but I swear I've tried every possible variation I could think up without success.
/* Standard C++ headers */
#include <iostream>
#include <sstream>
#include <memory>
#include <string>
#include <stdexcept>
#include <stdlib.h>
/* MySQL Connector/C++ specific headers */
#include <driver.h>
#include <connection.h>
#include <statement.h>
#include <prepared_statement.h>
#include <resultset.h>
#include <metadata.h>
#include <resultset_metadata.h>
#include <exception.h>
#include <warning.h>
#define DBHOST "removed"
#define USER "removed"
#define PASSWORD "removed"
#define DATABASE "removed"
#define NUMOFFSET 1
#define COLNAME 1
using namespace std;
using namespace sql;
static void retrieve_data_and_print (ResultSet *rs, int type, int colidx, string colname) {
/* retrieve the row count in the result set */
cout << "\nRetrieved " << rs -> rowsCount() << " row(s)." << endl;
cout << "\nTestColumnName" << endl;
cout << "--------" << endl;
/* fetch the data : retrieve all the rows in the result set */
while (rs->next()) {
if (type == NUMOFFSET) {
cout << rs -> getString(colidx) << endl;
} else if (type == COLNAME) {
cout << rs -> getString(colname) << endl;
} // if-else
} // while
cout << endl;
}
int main(int argc, const char *argv[]) {
Driver *driver;
Connection *con;
Statement *stmt;
ResultSet *res;
PreparedStatement *prep_stmt;
Savepoint *savept;
int updatecount = 0;
/* initiate url, user, password and database variables */
string url(argc >= 2 ? argv[1] : DBHOST);
const string user(argc >= 3 ? argv[2] : USER);
const string password(argc >= 4 ? argv[3] : PASSWORD);
const string database(argc >= 5 ? argv[4] : DATABASE);
try {
driver = get_driver_instance();
/* create a database connection using the Driver */
con = driver -> connect(url, user, password);
/* turn off autocommit */
con -> setAutoCommit(0);
cout << "Database connection\'s autocommit mode = " << con -> getAutoCommit() << endl;
// select database schema
con -> setSchema(database);
// create a statement object
stmt = con -> createStatement();
cout << "Executing Query: \"SELECT * FROM organizations\" ... " << endl;
/* run query */
res = stmt -> executeQuery ("SELECT * FROM organizations");
cout << "Retrieving the result set ..." << endl;
retrieve_data_and_print (res, NUMOFFSET, 1, string("TestColumnName"));
} catch (SQLException &e) {
cout << "ERROR: SQLException in " << __FILE__;
cout << " (" << __func__<< ") on line " << __LINE__ << endl;
cout << "ERROR: " << e.what();
cout << " (MySQL error code: " << e.getErrorCode();
cout << ", SQLState: " << e.getSQLState() << ")" << endl;
if (e.getErrorCode() == 1047) {
/*
Error: 1047 SQLSTATE: 08S01 (ER_UNKNOWN_COM_ERROR)
Message: Unknown command
*/
cout << "\nYour server does not seem to support Prepared Statements at all. ";
cout << "Perhaps MYSQL < 4.1?" << endl;
}
return EXIT_FAILURE;
} catch (std::runtime_error &e) {
cout << "ERROR: runtime_error in " << __FILE__;
cout << " (" << __func__ << ") on line " << __LINE__ << endl;
cout << "ERROR: " << e.what() << endl;
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
I was facing the same error because of incorrect linker,and maybe your linkers are not correct. Use these linkers
-lmysqlpp -lmysqlclient
Also you can follow this tutorial written by me on Eclipse (Ubuntu). Hope it will work with codeblocks too.
Here are a few of things you can try:
1. Try giving the linker an explicit name for your libs:
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\lib\opt\libmysqlcppconn.lib
C:\Program Files\MySQL\MySQL Connector C++ 1.1.7\lib\opt\libmysqlcppconn-static.lib`
Note: I added lib in front of those library names
Try linking in the dll for this instead of the static library if this doesn't work.
2. Try using MySQL_Driver instead of Driver(just for kicks):
#include <mysql_driver.h>
...
...
sql::mysql::MySQL_Driver *driver;
...
...
try
{
driver = sql::mysql::get_driver_instance();
3. You could try re-installing the connector c++ library from https://dev.mysql.com/downloads/connector/cpp/
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