title: How to implement a global incrementing id for multiple tables in SQL?
body: <p>I decided back when I was coding to have different tables for each type of content. Now I am stuck solving this. Basically my notification system ranks the newest content by its timestamp currently. This is inaccurate however because there is a small chance that someone would submit content at the same time as another person, and incorrect ranking would occur.</p>
  
  <p>Now if I had all my content in a single table, I would simply rank it by an auto-incrementing variable. Is there a way to implement this auto-increment integer across multiple tables (e.g. When something is inserted into <em>table1</em>, id=0, something is inserted into <em>table2</em>, id=1). Or do I have to recode all my stuff into a single table.</p>
  
  <p><strong>NOTE:</strong></p>
  
  <p>The reason I have content in multiple tables is because its organized and it would reduce load stress. I don't really care about the organization anymore, because I can just access the data through a GUI I coded, I'm just wondering about the load stress.</p>
  
  <p><strong>EDIT:</strong></p>
  
  <p>I'm using PHP 5 with MySQL.</p>