Comparing Rows

Hi,

The only way I can think of to do this is to create a cursor and somehow loop through the rows, comparing each column, and sum the totals. Does anyone know a more straightforward, easier way to accomplish?

I have a table where I have compare each column to see if something has changed for the same part. If so, the changes must be counted before or after a certain level - thereby, splitting the counts into 2 categories. I am using Oracle 9.2.0.3.0 on AIX platform.

The data is as follows. I need to determine how many iterations the part has gone through. A change made on any layer below 8 goes into category cnt 1, above 8 is catg2 cnt.

Part# Lvl# Layer Rev
----- ---- ----- ---

7239	9032	1	A            1st entry of part
7239	9032	2	A
7239	9032	3	A
7239	9032	3.9	A
7239	9032	4	A
7239	9032	4.5	A
7239	9032	5	A
7239	9032	6	A
7239	9032	6.05	A
7239	9032	7.1	A
7239	9032	8	A
7239	9032	9	A
7239	9032	10	A
7239	9032	11	A
7239	9032	12	A
7239	9032	13	A
7239	9032	15	A
7239	9032	30	A

7239	9199	1	A        compare to previous row for
7239	9199	2	A        same part, so this is rev 1
7239	9199	3	A
7239	9199	3.9	A
7239	9199	4	A
7239	9199	4.5	A
7239	9199	5	A
7239	9199	6	A
7239	9199	6.05	A
7239	9199	7.1	B        Change occurred below layer 8
7239	9199	8	B        Catg1 cnt = 1; catg2 cnt=0;
7239	9199	9	B
7239	9199	10	B
7239	9199	11	B
7239	9199	12	B
7239	9199	13	A
7239	9199	15	B
7239	9199	30	A

7239	9517	1	A
7239	9517	2	A
7239	9517	3	A
7239	9517	3.9	A
7239	9517	4	A
7239	9517	4.5	A
7239	9517	5	A
7239	9517	6	A
7239	9517	6.05	A
7239	9517	7.1	B
7239	9517	8	C       Change occurred above 8+ layer
7239	9517	9	C       catg1 cnt=1; catg2 cnt=1;
7239	9517	10	C
7239	9517	11	A
7239	9517	12	C
7239	9517	13	A
7239	9517	15	A
7239	9517	30	B

7239	10008	1	A
7239	10008	2	A
7239	10008	3	A
7239	10008	3.9	A
7239	10008	4	A
7239	10008	4.5	A
7239	10008	5	A
7239	10008	6	A
7239	10008	6.05	A
7239	10008	7.1	B
7239	10008	8	C       Change occurred above 8+ layer
7239	10008	9	C       Catg1 cnt = 1; catg2 cnt=2;
7239	10008	10	D
7239	10008	11	B
7239	10008	12	C
7239	10008	13	A
7239	10008	15	B
7239	10008	30	B