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    <p>Assuming the audit table also logs the <code>lease_period</code> primary key column, referenced here <code>lp_id</code> for simplicity, you could try the following approach:</p> <ol> <li><p>Find all the rows where <code>audit_type</code> is <code>'Updated'</code>.</p></li> <li><p>Rank all the rows by <code>audit_date</code> and partitioning them by <code>lp_id</code>.</p></li> <li><p>Rank the rows by <code>audit_date</code> partitioning by <code>lp_id, suite_id, lease_id, building_id</code>.</p></li> <li><p>Get the difference between the two rankings.</p></li> <li><p>Rank the rows again by <code>audit_date</code>, partitioning them now by <code>lp_id, suite_id, lease_id, building_id, (ranking_difference)</code>.</p></li> <li><p>Output all the rows where the last ranking value is 2 or greater.</p></li> </ol> <p>The first four steps result in a row set where each group of consecutive (in ascending order of <code>audit_date</code>) rows with identical values of <code>suite_id, lease_id, building_id</code> for the same <code>lp_id</code> will be uniquely distinguished by a value calculated as the difference between the rankings #2 &amp; #3.</p> <p>Within the group, every row, starting from the second one, will differ from the previous one only in the value of <code>tenant_trading_name</code>, which is just what we need. So, we rank the rows once again, taking into account the 'group ID' we've just obtained, then return every row with the ranking of 2 or higher.</p> <p>Here's an approximate implementation:</p> <pre><code>WITH marked AS ( SELECT *, grp = ROW_NUMBER() OVER (PARTITION BY lp_id ORDER BY audit_date) - ROW_NUMBER() OVER (PARTITION BY lp_id, suite_id, lease_id, building_id ORDER BY audit_date) FROM lease_period_audit WHERE audit_type = 'Updated' ), ranked AS ( SELECT *, rnk = ROW_NUMBER() OVER (PARTITION BY lp_id, suite_id, lease_id, building_id, grp ORDER BY audit_date) FROM marked ) SELECT audit_date, lp_id, tenant_trading_name, suite_id, lease_id, building_id FROM ranked WHERE rnk = 2 </code></pre> <p>Note. This assumes that the audit table logs only real changes, i.e. there can't be two consecutive rows with the same primary key where all four columns have identical values.</p>
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