我有这个小代码,我试图连接到一个数据库,它工作正常,现在我想选择/创建一个表,这也很好,但我不能出于任何原因选择一个特定的行。我不想循环遍历所有内容,我只想选择例如。列id
的第6行。
/* Standard C++ includes */
#include <stdlib.h>
#include <iostream>
#include <string>
/*
Include directly the different
headers from cppconn/ and mysql_driver.h + mysql_util.h
MySQL Connector/C++ Complete Example 2
37
(and mysql_connection.h). This will reduce your build time!
*/
#include "mysql_connection.h"
#include <cppconn/driver.h>
#include <cppconn/exception.h>
#include <cppconn/resultset.h>
#include <cppconn/statement.h>
using namespace std;
int main(void)
{
try {
sql::Driver *driver;
sql::Connection *con;
sql::Statement *stmt;
sql::ResultSet *res;
/* Create a connection */
driver = get_driver_instance();
con = driver->connect("tcp://127.0.0.1:3306", "root", "root");
/* Connect to the MySQL test database */
con->setSchema("server_database");
stmt = con->createStatement();
stmt->execute("CREATE TABLE testit(id INT, label CHAR(1))");
stmt->execute("INSERT INTO testit(id, label) VALUES (1, 'a')");
stmt->execute("INSERT INTO testit(id, label) VALUES (2, 'b')");
stmt->execute("INSERT INTO testit(id, label) VALUES (3, 'c')");
res = stmt->executeQuery("SELECT id, label FROM testit ORDER BY id ASC");
}
catch (sql::SQLException &e) {
cout << "# ERR: SQLException in " << __FILE__;
cout << "(" << __FUNCTION__ << ") on line " << __LINE__ << endl;
cout << "# ERR: " << e.what();
cout << " (MySQL error code: " << e.getErrorCode();
cout << ", SQLState: " << e.getSQLState() << " )" << endl;
}
cout << endl;
int aasd;
std::cin >> aasd;
return EXIT_SUCCESS;
}
我想知道,我如何选择特定的行,打印出来或做一些与他们。
1条答案
按热度按时间qco9c6ql1#
要选择行,请执行以下操作:n
在C++中:
别忘了: