database - 如何创建显示计算机拥有计算机程序的访问表？

Question

我是新来访问并尝试为我的公司创建数据库的人。我想创建的表之一是显示每台计算机的计算机程序需求的表。我有一个 Excel 表，其中行是计算机，列是程序。如果计算机拥有该程序，则有一个“x”（用于简单程序）或该程序的当前版本（例如 2.0.0.0）。我可以在访问中复制这张表，但我觉得我走错了路。有没有更好的方法来显示拥有多个程序的计算机？我需要能够创建有关软件版本的报告。将此类数据制成表格的最佳方法是什么？

Answer 1

You actually need four tables:

• computer: include details for each computer on its own (no programs), including primary key computer_id
• program: include details for each program on its own (no computers), including primary key program_id, but don't include the version number here
• program_version: this table has three columns: primary key version_id, foreign key program_id from table program, and version number
• computer_program: this table has two columns: foreign key computer_id from computer, and foreign key version_id from table program_version

To pull the data you'd need for your report, your query would probably look something like:

SELECT computer.make, program.vendor, program_version.version_num /* add other columns as needed */
    FROM computer_program cp
    INNER JOIN computer c ON cp.computer_id = c.computer_id
    INNER JOIN program_version pv ON cp.version_id = pv.version_id
    INNER JOIN program p ON pv.program_id = p.program_id
    WHERE c.make = 'Dell' OR pv.version_num = 4 OR p.vendor = 'Microsoft'