java - SQL : WHERE not working with JTable

Question

我正在使用 valueChanged() 将选定的 JTree 节点设置为 JTable，但我注意到使用 WHERE 时没有得到任何结果。删除 WHERE 后得到完整结果。

 @Override
public void valueChanged(TreeSelectionEvent tsl) {
    try {
        DefaultMutableTreeNode node = (DefaultMutableTreeNode) TestTree.getSelectionPath().getLastPathComponent();
     myTests_table.getModel();

        if (tsl.getNewLeadSelectionPath() != null) {
            if (node.isLeaf() != true) {
                //do nothing
            } else {
                String sql ="SELECT sub_group.name AS 'name', sub_group.price AS 'price'"
                        + "FROM sub_group"
                        + "WHERE sub_group.name = '"+node+"' "
                        + "ORDER BY sub_group.name ASC";

                pst = conn.prepareStatement(sql);
                rs = pst.executeQuery(sql);
                while (rs.next()) {
                    myTests_table.setModel(DbUtils.resultSetToTableModel(rs));
                }

                 System.out.println(node);
                JOptionPane.showMessageDialog(null, node);
                yy.setText(tsl.getNewLeadSelectionPath().getLastPathComponent().toString());

            }
        }
    } catch (Exception e) {
        JOptionPane.showMessageDialog(null, "Error");
    } finally {
        try {
            rs.close();
            pst.close();
        } catch (Exception e) {
            JOptionPane.showMessageDialog(null, "Some Error with connecting Database, Try again");
        }
    }
}

但是当我使用这条线时

+ "WHERE sub_group.name = '"+node+"' "

我的表是空的，那么有什么问题吗？!

Answer 1

代码不足以检查。更新总代码或执行 sysout 并更新结果，可能会看到错误是什么

 String sql ="SELECT sub_group.name AS 'name', sub_group.price AS 'price'"
                    + "FROM sub_group"
                    + "WHERE sub_group.name = '"+node+"' "
                    + "ORDER BY sub_group.name ASC";
System.out.println(sql);