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PODatabase tables, one table referencing multiple unrelated tables
 

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    <p>This question has come up a few times in various forums in my searching, but none have provided a concise resolution.</p> <p>If I have the following tables:</p> <pre><code>User +- id +- username +- password Article +- id +- title +- content </code></pre> <p>and I want to join them in order to determine who created what articles, I could simply add the column <strong>user_id</strong> to <strong>Article</strong> to use as a reference. Alternatively, I'm adding an intermediate table to show who/when/what, for example:</p> <pre><code>User +- ... Article +- ... ChangeHistory +- id +- article_id +- user_id +- type [enum(insert, update, delete)] +- datetime </code></pre> <p>Now this is fine, but the system I'm working on needs to be much more dynamic, in that new modules can be easily introduced and integrated. So now if I add a <strong>Media</strong> table I need to split the <strong>ChangeHistory</strong> between <strong>Article</strong> and <strong>Media</strong> having:</p> <pre><code>User +- ... Article +- ... Media +- id +- title +- path ArticleChangeHistory +- id +- article_id +- user_id +- type [enum(insert, update, delete)] +- datetime MediaChangeHistory +- id +- media_id +- user_id +- type [enum(insert, update, delete)] +- datetime </code></pre> <p>This can get out of hand quickly with the introduction of many modules. Each module would need to be responsible for the creation and management of it's own <strong>ChangeHistory</strong> table.</p> <p><strong>TL;DR: What practices can I explore to create an intermediate table that can receive references to multiple other unrelated tables? I could add a *record_type* field, holding the name of the table to which the record belongs, but that's ugly. I would need something like a "<em>table ID</em>" to reference the table from which it's coming. That way, when/if modules are added or removed, the model doesn't fall apart.</strong></p> <p>Any ideas? Thanks so much in advance.</p>
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    1. USDan Lugg
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    1. COIs there some reason that you consider a "table ID" to be better than a "record_type"?
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      1. USTom H
 

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