Question

您好我在oracle中对表运行一个简单的select查询并获取结果集。比如select username, responsibility, project from mytable.
结果集包含用户详细信息。为每个用户名返回多行，其中包含责任和项目的不同值。现在我想从这个结果集中获取一个列表，每个用户名都有一个List，不同的值以逗号分隔的字符串连接。
因此，如果Sam在结果集中有多个条目，那么我的操作输出应该给我：

UserList =
["Sam", "responsibility1,responsibility2,responsibility3...", "dept1,dept2,dept3.."],
[Some other User],
[and so on..]

稍后我会将其写入csv文件出于兼容性原因，我无法在查询本身中执行此操作，我们将来必须支持多个数据库版本我如何在java或groovy中这样做？

由于

Answer 1

Java非常简单。您需要一个类来为每个用户建模。您需要用户名的地图。每个用户都包含责任清单和部门清单。然后迭代结果集，从每行的地图中找到用户，并将责任和部门添加到该用户

您需要代码还是足够好？

HTH

编辑：这是一些Java启动代码：（未检查语法或错误;]）

public class User {
    private final List<String> responsibility = new ArrayList<String>();
    private final List<String> department = new ArrayList<String>();

    ...standard getters and setters
}

// Your code to do the read
public void executeRead() {

    ... obtain the resultset somehow here

    Map<String, User> usernameToUser = new HashMap<String, User>():
    while (rs.next) {
        String username = rs.getString("username");
        User user = usernameToUser.get(username);
        if (user == null) {
            user = new User(); // Create and remember a user the first time you see them
            usernameToUser.put(username, user);
        }
        String responsiblity = rs.getString("responsiblity");
        String department = rs.getString("department");
        user.addResponsibility(responsibility);
        user.addDepartment(department);
    }
    rs.close();

    // Now you have the data structure of users in memory you can output
    // it in whichever format you like e.g. HTML, CSV, etc
    // Probably best to do this step in a totally separate place that can
    // be switched out for a different output format in future.
}

groovy脚本/ java代码，以从结果集中获取不同的用户

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