Control exceptions or errors in procedure

Question

Hy , I have a proceducre like this:
CREATE OR REPLACE PROCEDURE "MY_PROCEDURE"( )
AS
BEGIN
INSERT INTO tableBackupTable1 SELECT table1.* FROM table1;
INSERT INTO tableBackupTable2 SELECT table1.* FROM table2;
*/*Disable FK*/*
for i in (select constraint_name, table_name from user_constraints where constraint_type ='R' and status = 'ENABLED')
LOOP
          execute immediate 'alter table '||i.table_name||' disable constraint '||i.constraint_name||'';
end loop;
delete * from table1;
delete * from table2;
*/*Enable FK*/*
for i in (select constraint_name, table_name from user_constraints where constraint_type ='R' and status = 'ENABLED')
LOOP
          execute immediate 'alter table '||i.table_name||' enable constraint '||i.constraint_name||'';
end loop;
END;
1. If I want to control the errors or exceptions for this procedure from my java code where Im calling this procedure from:
I dont have to declare a block "EXCEPTION......" in the procedure, right?
2. If I want to rollback if an error or exception happens, should I do something in the procedure or in my java code?
3. If I dont want to return anything in my procedure, should I use a sys_refcursor like out parameter?
4. Should I use commit, where?
5. Should I surround the loops for enable or disable fk with begin and end because If I dont surround it and an error ocurrs while enablling FK or disabling them ?
6. All my accesses to the database from my java code are transactional, so if I call this procedure from my java code and this call is transactional and the procedure is itself transactional, is there a problem with this?
Thanks
Edited by: user13162080 on 29-dic-2010 6:40
Edited by: user13162080 on 29-dic-2010 6:46
Edited by: user13162080 on 29-dic-2010 6:56

Answer 1

Hi,
I dont want to handle it in the procedure itself because I am controlling all exceptions or errors in the database from java to make rollback or whatever
Can you help me in the others questions? In my opinion this is not the right way to handle database exception. Database exception should be handled in database itself not in java. Oracle will rollback the transaction autometically if any statement fails(exception) and you will not have to put extra efforts(java code) to control the exception. If you wish you can explain your business requirement we may suggest something easier/better.
2. If I want to rollback if an error or exception happens, should I do something in the procedure or in my java code?It should be driven by your business requirement.
3. If I dont want to return anything in my procedure, should I use a sys_refcursor like out parameter?It depends what kind of value you want to return. For a single value sys_refcursor is not the right tool. Refer this link http://download.oracle.com/docs/cd/E11882_01/appdev.112/e17126/static.htm#i7106
4. Should I use commit, where?
It should also driven by your business need. COMMIT will make the changes permanent into the database so whenever you want to commit you can. All the DDLs (CREATE, DROP table etc) are having implicit (auto) COMMIT.
5. Should I surround the loops for enable or disable fk with begin and end because If I dont surround it and an error ocurrs while enablling FK or disabling them ?
I would suggest to have a look on http://download.oracle.com/docs/cd/E11882_01/appdev.112/e17126/toc.htm
6. All my accesses to the database from my java code are transactional, so if I call this procedure from my java code and this call is transactional and the procedure is itself transactional, is there a problem with this?
What do you mean by transactional? do you mean for each row?
Thanks and Regards,
Avinash
Edited by: Avinash Tripathi on Dec 29, 2010 7:04 PM