title: Find two consecutive rows
body: <p>I'm trying to write a query that will pull back the two most recent rows from the Bill table where the Estimated flag is true. The catch is that these need to be consecutive bills. </p>
  
  <p>To put it shortly, I need to enter a row in another table if a Bill has been estimated for the last two bill cycles.</p>
  
  <p>I'd like to do this without a cursor, if possible, since I am working with a sizable amount of data and this has to run fairly often.</p>
  
  <p><strong>Edit</strong></p>
  
  <p>There is an AUTOINCREMENT(1,1) column on the table.  Without giving away too much of the table structure, the table is essentially of the structure:</p>
  
  <pre><code>
  CREATE TABLE Bills (
    BillId INT AUTOINCREMENT(1,1,) PRIMARY KEY,
    Estimated BIT NOT NULL,
    InvoiceDate DATETIME NOT NULL
  )
  </code></pre>
  
  <p>So you might have a set of results like:</p>
  
  <pre>
  BillId               AccountId            Estimated InvoiceDate
  -------------------- -------------------- --------- -----------------------
  1111196              1234567              1         2008-09-03 00:00:00.000
  1111195              1234567              0         2008-08-06 00:00:00.000
  1111194              1234567              0         2008-07-03 00:00:00.000
  1111193              1234567              0         2008-06-04 00:00:00.000
  1111192              1234567              1         2008-05-05 00:00:00.000
  1111191              1234567              0         2008-04-04 00:00:00.000
  1111190              1234567              1         2008-03-05 00:00:00.000
  1111189              1234567              0         2008-02-05 00:00:00.000
  1111188              1234567              1         2008-01-07 00:00:00.000
  1111187              1234567              1         2007-12-04 00:00:00.000
  1111186              1234567              0         2007-11-01 00:00:00.000
  1111185              1234567              0         2007-10-01 00:00:00.000
  1111184              1234567              1         2007-08-30 00:00:00.000
  1111183              1234567              0         2007-08-01 00:00:00.000
  1111182              1234567              1         2007-07-02 00:00:00.000
  1111181              1234567              0         2007-06-01 00:00:00.000
  1111180              1234567              1         2007-05-02 00:00:00.000
  1111179              1234567              0         2007-03-30 00:00:00.000
  1111178              1234567              1         2007-03-02 00:00:00.000
  1111177              1234567              0         2007-02-01 00:00:00.000
  1111176              1234567              1         2007-01-03 00:00:00.000
  1111175              1234567              0         2006-11-29 00:00:00.000
  </pre>
  
  <p>In this case, only records 1111188 and 1111187 would be consecutive.</p>