Question

Possible Duplicate:
how to join 2 tables

I am very new to databases. I am trying two link to tables together, using a third map table. How do I go about doing this in oracle?
Thank you.

Answer 1

Assuming two tables A and B that have IDs of type INT…

CREATE TABLE A (
  ID INT,
  ...
)

CREATE TABLE B (
  ID INT,
  ...
)    

You would map them with:

CREATE TABLE ABCrossReference (
  A_ID INT,
  B_ID INT
)

And store A.ID in ABCrossReference.A_ID and B.ID in ABCrossReference.B_ID

Finally you would JOIN them together to get the data:

SELECT * FROM A
JOIN ABCrossReference ON A.ID = ABCrossReference.A_ID
JOIN B ON ABCrossReference.B_ID = B.ID