What will be the query to generate this reports ?

Question

Dear Exparts,
Here is my banner
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Prod
PL/SQL Release 10.2.0.3.0 - Production
"CORE     10.2.0.3.0     Production"
TNS for 32-bit Windows: Version 10.2.0.3.0 - Production
NLSRTL Version 10.2.0.3.0 - ProductionHere is the sample data
TId     TDate               TName     TCol1     TCol2     TCol3     TCol4     TCol55     TCol56     TCol N
1     01-aug-2012     Abc     Ab     Bc     aa     bb               TT
2     05-aug-2012     abc     A     A     aa     bb               TT
3     20-aug-2012     bcd     AA     AA     BB     bb     C     D     TTI want to produce the following report
Revision Date     Revision Field     Previous Value     Revised Value
05-aug-2012     TCol1                Ab                  A
                TCol2                Bc                  A
20-aug-2012     TName                      Abc           Bcd
                TCol1                A                   AA
                TCol2                A                   AA
                TCol3                Aa                  BB
                TCol55                                   C
                TCol56                                DHow can i do this... ?
Here is the script for create table
CREATE TABLE TB_TEST
  TID NUMBER(5)
, TDATE DATE
, TNAME VARCHAR2(20)
, TCOL1 VARCHAR2(20)
, TCOL2 VARCHAR2(20)
, TCOL3 VARCHAR2(20)
, TCOL4 VARCHAR2(20)
, TCOL55 VARCHAR2(20)
, TCOL56 VARCHAR2(20)
, TCOLN VARCHAR2(20)
);Script for sample data
INSERT INTO TB_TEST (TID,TDATE,TNAME,TCOL1,TCOL2,TCOL3,TCOL4,TCOLN)
VALUES (1,TO_DATE('01-AUG-2012','DD-MON-RRRR'),'ABC','AB','BC','AA','BB','TT');
INSERT INTO TB_TEST (TID,TDATE,TNAME,TCOL1,TCOL2,TCOL3,TCOL4,TCOLN)
VALUES (2,TO_DATE('05-AUG-2012','DD-MON-RRRR'),'ABC','A','A','AA','BB','TT');
INSERT INTO TB_TEST (TID,TDATE,TNAME,TCOL1,TCOL2,TCOL3,TCOL4,TCOL55,TCOL56,TCOLN)
VALUES (3,TO_DATE('20-AUG-2012','DD-MON-RRRR'),'BCD','AA','AA','BB','BB','C','D','TT');Thanks..
Edited by: Asked to Learn on Sep 9, 2012 6:57 PM

Answer 1

Hi,
Asked to Learn wrote:
Dear Exparts,
Here is my banner ...Thanks; that's helpful.
Here is the sample data
Id     Date               Name     Col1     Col2     Col3     Col4     Col55     Col56     Col N
1     01-aug-2012     Abc     Ab     Bc     aa     bb               TT
2     05-aug-2012     abc     A     A     aa     bb               TT
3     20-aug-2012     bcd     AA     AA     BB     bb     C     D     TT
That's not so helpful. Whenever you have a question, post CREATE TABLE and INSERT statements for the sample data. See {message:id=9360002}
I want to produce the following report
Revision Date     Revision Field     Previous Value     Revised Value
05-aug-2012     Col1                Ab                  A
Col2                Bc                  A
20-aug-2012     Name              Abc                Bcd
Col1                A                   AA
Col2                A                   AA
Col3                Aa                  BB
Col55                              C
Col56                                DHow can i do this... ?First, Unpivot the data so that, instead on having 8 columns of comparison data on 1 row, you have 1 column on 8 rows. Since you're using Oracle 10.2, you can't use the SELECT ... UNPIVOT feature, but there are other ways to unpivot. See {message:id=10562807} for a technique that works in Oracle 9.1 or higher.
Then, use the anlytic LAG function to compare each vlaue to its previous value. You can do the same sort of thing with the revision_date column, to display NULL when it's the same as the previous row.
If you'd like help, post CREATE TABLE and INSERT statmements for the sample data, and your best attempt. Simplify the problem at first. Just unpivot name and col1: forget about col2 through coln for now. Once you have a solution for 2 columns, modifying it for 8 (or 9, or 89) columns will be easy. When you can unpivot the 2 columns, see if you can use LAG to compare them.