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【DM版本】:8
【操作系统】：win7
【CPU】:intel
【问题描述】*：我的代码如下，就是ResultSet rs里面没有数据，用DM管理工具是有数据的，而且提示链接成功，如果把表名改了的话就会提示无效的表或视图名
public class DM_jdbc_conn {
static Connection con = null;
static String cname = "dm.jdbc.driver.DmDriver";
static String url = "jdbc:dm://localhost:5236/TEST";
static String userid = "TEST";
static String pwd = "123456789";

public static void main(String[] args) {
try {
Class.forName(cname);
con = DriverManager.getConnection(url, userid, pwd);
con.setAutoCommit(true);
System.out.println("[SUCCESS] connect database");

Statement stmt = con.createStatement();
String sql = "SELECT * FROM city WHERE city_name='北京';";
PreparedStatement preparedStatement = con.prepareStatement(sql);
ResultSet rs = preparedStatement.executeQuery();
List data = new ArrayList<>();
while(rs.next()){
System.out.println(""有效" = " + "有效"+rs.getInt("c"));
data.add(rs.getString("info"));
}
rs.close();
stmt.close();
} catch (Exception e) {
System.out.println("[FAIL] connect database: " + e.getMessage());
} finally {
try {
disConn(con);
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void disConn(Connection con) throws SQLException {
if (con != null) {
con.close();
}
}
}