title: HBase performance with large number of dynamically generated column qualifiers (within a column family)
body: <p>I have a table with 1 column family called 'A'.
  On runtime, I will insert the (Key-Value) pair to the table.
  Leave the RowKey away, in my design, <strong>Column qualifier</strong> is MD5(Key) <strong>so, column qualifers are dynamically created</strong>, and <strong>the cell</strong> will contains the corresponding Value.</p>
  
  <p>E.g: Each car has a license plate. I want to insert all to one table in HBase. Car A has <em>rowkey</em> R1, <em>column qualifier</em> is C1, <em>value</em> is License Plate of A. Car B has <em>rowkey</em> R2, , <em>column qualifier</em> is C2, <em>value</em> is License Plate of A, and vice versa. With the schema, When executing <strong>Scan</strong> command, with <em>rowkey</em> = R1, is cell contained in <em>column qualifier</em> C2 return (in this case, it is definite null)?</p>
  
  <p>I want to ask some questions about performances:</p>
  
  <ol>
  <li><p>With this schema design, Does <strong>Scan</strong> command's performance decrease? (I want to scan all values on the table). With each row, is all column will be returned?</p></li>
  <li><p>With the above requirements, can anyone point me the right way to design this table?</p></li>
  </ol>
  
  <p>Thank you very much!</p>