Question

有人可以帮帮我吗？我正在尝试在创建记录时检索ID（主键）并将其设置为文本字段。目前，它返回的所有时间都是1。我目前的方法如下：

connection = Utilities.getConnection();
            String sqlQuery = "INSERT INTO student_details (Name, Surname, Date_Of_Birth, Gender, Address, Post_Code, Mobile_Number)" + " VALUES (?, ?, ?, ?, ?, ?, ?)";
            preparedStatement = connection.prepareStatement(sqlQuery);
            preparedStatement.setString(1, txtFirstName.getText().trim());
            preparedStatement.setString(2, txtSurname.getText().trim());
            preparedStatement.setString(3, String.valueOf(dpDateOfBirth.getValue()));
            preparedStatement.setString(4, cbGender.getSelectionModel().getSelectedItem().toString());
            preparedStatement.setString(5, txtAddress.getText().trim());
            preparedStatement.setString(6, txtPostCode.getText().trim());
            preparedStatement.setString(7, txtMobileNo.getText().trim());
            preparedStatement.executeUpdate();
            txtStudentID.setText(String.valueOf(preparedStatement.RETURN_GENERATED_KEYS));
            Utilities.showInforMsg("Record Saved:", "Record has been saved.");

Answer 1

您应该通过以下方式获取生成的密钥：

ResultSet rs = preparedStatement.getGeneratedKeys();

if (rs.next()) {
    key = rs.getLong(1);
}

你正在用这条线做什么

txtStudentID.setText(String.valueOf(preparedStatement.RETURN_GENERATED_KEYS));

将学生ID设置为Statement接口常量的值（请参阅此处https://docs.oracle.com/javase/7/docs/api/java/sql/Statement.html#RETURN_GENERATED_KEYS）

Java / MySQL - 从保存的上一条记录中检索ID

1 个答案: