Do I need an Index?

If I have a table that is defined as:

CREATE TABLE ORGS
(

NUM	INTEGER	NOT NULL,
ID	INTEGER	NOT NULL

and both "num" and "id" REFERENCES other tables to make sure theie data exist there before being in this table defined like:

ALTER TABLE ORGS
ADD CONSTRAINT XFK_NUM FOREIGN KEY (NUM)

		REFERENCES NUM_TABLE(NUM)
		ON DELETE CASCADE

ALTER TABLE ORGS
ADD CONSTRAINT XFK_ID FOREIGN KEY (ID)
                REFERENCES ID_TABLE(ID) So, the data in ORGS would look something like:

1,99
1,98
1,97
2,99

So, my question: If I am using a query to pull data using the ID, i.e. 98, or 97 would an index speed up the processing or is there an inate index by virtue of there being a reference there?

Any comments appreciated.

Mike Received on Wed Aug 10 2005 - 10:44:53 CDT