Query Performance issue in Oracle Forms

Question

Hi All,
I am using oracle 9i DB and forms 6i.
In query form ,qry took long time to load the data into form.
There are two tables used here.
1 table(A) contains 5 crore records another table(B) has 2 crore records.
The recods fetching range 1-500 records.
Table (A) has no index on main columns,after created the index on main columns in table A ,the query is fetched the data quickly.
But DBA team dont want to create index on table A.Because of table space problem.
If create the index on main table (A) ,then performance overhead in production.
Concurrent user capacity is 1500.
Is there any alternative methods to handle this problem.
Regards,
RS

Answer 1

1) What is a crore? Wikipedia seems to indicate that it's either 10,000,000 or 500,000
http://en.wikipedia.org/wiki/Crore
I'll assume that we're talking about tables with 50 million and 20 million rows, respectively.
2) Large tables with no indexes are definitely going to be slow. If you don't have the disk space to create an appropriate index, surely the right answer is to throw a bit of disk into the system.
3) I don't understand the comment "If create the index on main table (A) ,then performance overhead in production." That seems to contradict the comment you made earlier that the query performs well when you add the index. Are you talking about some other performance overhead?
Justin