title: Finding overlapping and calculation of min and max dates with in overlap in oracle
body: <p>How can we find the between the overlap lap b/w the dates .
  overlap means when start date and end date are within same range
  for below example row 1  has no over lap.
  Row 2to 5 can be considered as one set of over lap as there start date and end are over lap with themselves
  Row 6 &amp; 7 can be considered as one set of over lap
  for eg. row 6 &amp; 7 --&gt; start date of row 7  is in same range  with respect to end date of row 6
  so it becomes an overlap</p>
  <p>Once overlap is found then and need to find out min(start date) and max(end date) and<br />
  want to assign a unique id to each overlap and in the <strong>S.NO</strong> column should show which rows are overlapped .Below is the I/p and O/p</p>
  <hr />
  <p>I/p
  <a href="https://i.stack.imgur.com/c4s7Q.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/c4s7Q.png" alt="enter image description here" /></a></p>
  <p><a href="https://i.stack.imgur.com/NiXJ6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/NiXJ6.png" alt="enter image description here" /></a></p>