Data not inserted into the sqlite table c++ - c++

Question

I am trying to save the contents of the key and value of a map into a database table. The .dbo file is created, but nothing goes into the table. It doesn't create table but it doesn't exit. I wonder what is wrong with my code.
void names_table( std::map<std::string, unsigned int> &names ){
std::string sql;
std::string str1;
std::string str2;
std::string str3;
sqlite3_stmt *stmt;
const char *file_names = create_db_file( ); /* default to temp db */
sqlite3 *db;
sqlite3_initialize( );
int rc = sqlite3_open_v2( file_names, &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL);
if ( rc != SQLITE_OK) {
sqlite3_close( db );
cout << "Error: Database cannot open!" << endl;
exit( EXIT_FAILURE);
}
sql = "CREATE TABLE IF NOT EXISTS names_table (offset INTEGER PRIMARY KEY, stname TEXT);";
sqlite3_prepare_v2(db, sql.c_str(), sql.size(), &stmt, NULL);
if (sqlite3_step(stmt) != SQLITE_DONE) cout << "Didn't Create Table!" << endl;
for (auto pm = names.begin(); pm != names.end(); pm++) {
str2 = "'" + pm->first + "'";
char tmp[15];
sprintf(tmp,"%u",pm->second);
str3 = tmp;
str1 = (((("INSERT INTO names_table VALUES(" + str3) + ", ") + str2) + ");");
std::cout << str1 << std::endl;
sql = (char *)str1.c_str();
// stmt = NULL;
rc = sqlite3_prepare_v2(db, sql.c_str(), sql.size(), &stmt, NULL);
if ( rc != SQLITE_OK) {
sqlite3_close(db);
cout << "Error: Data cannot be inserted!" << endl;
exit ( EXIT_FAILURE);
}
}
sqlite3_close( db );
}

Answer 1

INSERT INTO names_table VALUES(ramsar, 8329) - I hope you're aware that string literals in SQL need to be enclosed in quotes. Try this: INSERT INTO names_table VALUES('ramsar', 8329).
EDIT: Actually, your code will never do what you want, because you're not even calling sqlite3_step after sqlite3_prepare_v2, which means that you're only compiling your SQL statement, but never evaluating it. Where did you find this bad example? See here and here decent examples on how to use the SQLite C++ interface properly.
PS: Stop messing around with sprintf in C++. You have std::stringstream for it.