sqlzoo List the film title and the leading actor for all of the films 'Julie Andrews' played in.

SQLZoo 是一个在线学习 SQL 的平台，你可以通过编写 SQL 查询来获取电影标题（film_title）和她（Julie Andrews）作为主角的电影的男主角名字（leading_actor）。这个问题假设数据库中有足够的信息存储了演员、电影以及他们各自的角色。

查询示例（假设有一个名为 `movies` 的表，其中包含 `title`, `lead_actor` 和 `actor_name` 列）：

SELECT movies.title AS film_title, movies.lead_actor AS leading_actor
FROM movies
JOIN roles ON movies.id = roles.movie_id
WHERE roles.actor_name = 'Julie Andrews';

这条查询将 `movies` 表与 `roles` 表关联起来，查找 `actor_name` 为 'Julie Andrews' 的记录，并返回对应的电影标题和男主角（通常电影中主角的演员会出现在 lead_actor 列）。

相关问题

Develop a use case for the activity of change user password for a website

A use case for the activity of changing a user's password for a website could be as follows:

Title: Change User Password

Primary Actor: Registered User

Goal in Context: The registered user wants to change their password for the website.

Preconditions:
- The registered user is logged in to their account.
- The website has a feature to change the user's password.

Trigger: The registered user clicks on the "Change Password" button on the website.

Main Success Scenario:
1. The website displays the "Change Password" form.
2. The registered user enters their current password, new password, and confirms the new password.
3. The website validates the entered passwords.
4. If the entered passwords are valid, the website updates the user's password and displays a success message.
5. If the entered passwords are invalid, the website displays an error message.

Extensions:
- If the user enters an incorrect current password, the website displays an error message and prompts the user to enter the correct password.
- If the user enters a new password that does not meet the website's password requirements, the website displays an error message and prompts the user to enter a valid password.

Postconditions:
- The registered user's password is updated in the website's database.
- The registered user can log in to their account using their new password.

6. What is the State chart Diagram? Explain the following. a. Process b.Data Flows c. Actor d.Data Stores

State chart diagram is a graphical representation of the states and state transitions of a system. It describes the behavior of a system over time and helps to model the dynamic aspects of a system.

a. Process: A process is a set of activities that are performed to achieve a specific goal. In a state chart diagram, a process is represented by a rectangular box with rounded corners. It shows the steps involved in achieving the goal of the system.

b. Data Flows: Data flows are the movement of data from one part of the system to another. In a state chart diagram, data flows are shown as arrows with labels that represent the data being transferred. Data flows can be used to represent inputs, outputs, and intermediate data.

c. Actor: An actor is a person, organization, or system that interacts with the system being modeled. In a state chart diagram, an actor is represented by a stick figure. Actors can be used to represent users, other systems, or external entities that interact with the system.

d. Data Stores: A data store is a repository of data that is used by the system. In a state chart diagram, a data store is represented by a rectangle with two parallel lines at the top and bottom. Data stores can be used to represent databases, files, or other storage mechanisms used by the system.