title: Why inner join too slow?
body: <p>I've tested both Microsoft Access and Microsoft SQL Compact with ADODB.</p>
  
  <p>I have a table tblCustomer for storing customer information </p>
  
  <pre><code>tblCustomer structure
  --------------------
  ID  Name  Email        Something...
  1   ABC   ABC@ABC.com  Something....
  </code></pre>
  
  <p>And a tblTag for categories customer into many types . For example rich customer: tag id = 1 , debt customer : tag id  =2 . Each customer can have one or both tag.</p>
  
  <pre><code>tblTag structure
  --------------------
  ID  TagID  CustomerID
  1   1      1
  2   2      1
  </code></pre>
  
  <p>And then i already added index for column ID, TagID, CustomerID for those table.</p>
  
  <p>But when i using this query for getting all customer that are rich. The query take me 8000ms with total 170.000 records in tblCustomer.</p>
  
  <pre><code>Select * from tblCustomer INNER JOIN tblTag on
  tblTag.CustomerID=tblCustomer.ID where tblTag.TagID=1
  </code></pre>
  
  <p>If i run only <code>Select * from tblCustomer</code> , it's only take me 3000 ms. It's even faster when i get all table. Inner join is not running as my expected. And 8000 ms is too slow with me when the customer can grow up to 1.000.000 record and i don't want my program stun a minute for each time run this query. So may be i've wrong when create a table Tag? Should i bring the tag into tblCustomer as a column like Rich (bit) or Debt (bit) ? </p>