How to find the list of un used table names in a schema?

Question

Hi,
I have a doubt in Oracle. The doubt is that If we are using any tables in Function Or Proc.... Then...We can list all those used table names from USER_DEPENDENCIES system table. Right...
But, If the table is used with Execute Immediate Statement, then, those table names are not coming out with USER_DEPENDENCIES system table. Because they are identified at run time and not compile time.
It is fine. And I agree.. But, If I want to list out those tables also...then...How to do? Any idea?
I think ‘USER_SOURCE’ system table may not be the right one. If there is any other system table avails for this purpose...then..it would be very grateful to extract right...
So I am wanting that exact system table.
Please let me know about this, if you have any idea or check with your friends if they have any idea.
Regards,
Subramanian G

Answer 1

Hi Guys,
Thanks for all your answers.
Yes....You are all right. We can list out the used tables upto certain extent. Anyhow, I have done some R&D to derive the SQL's which is given below:
SELECT TABLE_NAME FROM USER_TABLES
MINUS
SELECT DISTINCT UPPER(REFERENCED_NAME)
FROM user_dependencies
where
referenced_type='TABLE' and UPPER(NAME) in
select distinct UPPER(object_name) from user_objects where UPPER(object_type) in
'MATERIALIZED VIEW',
'PACKAGE',
'PACKAGE BODY',
'PROCEDURE',
'TRIGGER',
'VIEW',
'FUNCTION'
UNION
SELECT UT.TABLE_NAME FROM
SELECT TABLE_NAME FROM USER_TABLES
MINUS
SELECT DISTINCT UPPER(REFERENCED_NAME)
FROM user_dependencies
where
referenced_type='TABLE' and UPPER(NAME) in
select distinct UPPER(object_name) from user_objects where UPPER(object_type) in
'MATERIALIZED VIEW',
'PACKAGE',
'PACKAGE BODY',
'PROCEDURE',
'TRIGGER',
'VIEW',
'FUNCTION'
AND REFERENCED_OWNER=(SELECT sys_context('USERENV', 'CURRENT_SCHEMA') FROM dual)
) UT,
( SELECT * FROM USER_SOURCE
WHERE NAME IN
( SELECT DISTINCT NAME FROM USER_SOURCE
WHERE TYPE NOT IN ('TYPE')
AND
UPPER(TEXT) LIKE '%EXECUTE IMMEDIATE%'
) US
WHERE
UPPER(US.TEXT) LIKE '%'||UPPER(UT.TABLE_NAME)||'%'
AND
(UPPER(US.TEXT) NOT LIKE '%--%')
The above SQL Query can list out unused tables by checking the Dynamic SQL Statement also upto some level only.
Once we extracted the list of unused tables, having a manual check would be also greater to verify as it is should not impact the business applications.
Regards,
Subramanian G