这是可能的。只需使用一个额外的连接和语句。

This is possible. Just use an extra connection and statement.

Statement statementOne = connectionOne.createStatement();
Statement statementTwo = connectionTwo.createStatement();
ResultSet resultSetOne = statementOne.executeQuery("select * from x");

while (resultSetOne.next()) {
    ResultSet resultSetTwo = statementTwo.executeQuery(String.format("select * from y where xy = %s", resultSetOne.getString(0)));

    while (resultSetTwo.next()) {
        String result = resultSetTwo.getString(0);
    }
}