Comaparing Data within Tables in Database

Question

Hi All,
I need to write a PL/SQL Procedure to Compare Data within Tables in a Database.
For Ex :- There is two tables A and B . A has id as 101 and B has is has 101. I need to comapre the Data . If no match is found within the tables i need to have those table name and column name printed. Please help.

Answer 1

Assuming that you want to compare tables with identical structure here is one query that will give you all the records that exist in TABLE_A but do not in TABLE_B
select 'exist in A but doesn't in B' desc, a.*
from TABLE_A a
MINUS
select 'exist in A but doesn't in B' desc, b.*
from TABLE_B bfrom the other hand if you want to get the oposite result you can transform the query above to
select 'exist in B but doesn't in A' desc, b.*
from TABLE_B b
MINUS
select 'exist in B but doesn't in A' desc, a.*
from TABLE_A afinally, if you want to get all the records that are missing in some of the tables, you can do a UNION of the queries above:
select 'exist in A but doesn't in B' desc, a.*
from TABLE_A a
MINUS
select 'exist in A but doesn't in B' desc, b.*
from TABLE_B b
UNION
select 'exist in B but doesn't in A' desc, b.*
from TABLE_B b
MINUS
select 'exist in B but doesn't in A' desc, a.*
from TABLE_A aNow the question is, which records do you want to print?
Also this query might work quite slow if TABLE_A and TABLE_B are large tables.
I hope this will give you some ideas.