SQL QUESTION

From: Jean-Marc Boivin <jmboivin_at_cti.ulaval.ca>
Date: Tue, 23 Nov 1993 19:44:38 GMT
Message-ID: <jmboivin.3.000EBEEA_at_cti.ulaval.ca>

Hi!
Please, help me with this SQL problem:

I have a table similar to this:

table_x

    begin_date date,
    end_date date

Suppose i have the following rows in this table:

begin_date              end_date
---------------------           ---------------------------
1-nov-93                  10-nov-93
11-nov-93                 13-nov-93
18-nov-93                 30-nov-93

As you can see there is a break in the sequence of dates between the 13-nov-93 and the 18-nov-93 (ie: no row covert this period). I want a SQL statement which will return each existing row as a 'occupied period' and periods not covered by row as 'free period'. So the result should be like this:

begin_date                end_date        status
-------------------               -------------------    ----------
1-nov-93                    10-nov-93       OCC
11-nov-93                  13-nov-93       OCC
14-nov-93                  17-nov-93       FREE
18-nov-93                  30-nov-93       OCC

anybody know how to do it with a sql statement ?(please no PL*SQL since it will be used to build a view.)

Thank's

---

Jean-Marc Boivin
System analyst
Universite Laval
Quebec, Canada
mail: jmboivin_at_cit.ulaval.ca
tel: (418) 656 3632

---

Received on Tue Nov 23 1993 - 20:44:38 CET