title: Multiple inner joins with multiple tables
body: <p>So I have four tables. Each table has a single id for the previous table id. So my in click table has an id and an id for the ad from which it came. In the ad table, it has an id for the ad and one for the campaign it's from. So here's an example.</p>
  
  <pre><code>Table4 -
  id   company      table_id
  11     hp           20
  12     apple        23
  13     kohls        26  
  14     target       21
  15     borders      28
  
  Table3 - 
  id    value    table2_id
  21     ks          53
  22     al          54
  23     tx          53 
  24     fl          55
  25     co          51
  
  Table2 -
  id    value    table1_id
  51     ks          34
  52     al          34
  53     tx          33 
  54     fl          35
  55     co          31
  
  Table1 -
  id    value    
  31     ks        
  32     al          
  33     tx          
  34     fl          
  35     co  
  </code></pre>
  
  <p>So to find out where the values in Table 4 came from, I need to work back through each table and check which id they have. Basically, I want to know which values in table 1 are associated with the values in table 4.</p>
  
  <p>This of table 4 as visitors to a website and Table 1 as internet ads. I want to know which visitors came from which ads. Unfortunately, the data is set up so that I can only take single steps back from visitor to source to ad group to ad. Does that make sense?</p>
  
  <p>Anyways, I'm wondering if using 4 innner joins was the optimal strategy for this problem or is there some simpler mysql solution that i'm not aware of.</p>