Use of second table

Question

HI I need to get some data from a second table in Oracle 10G test system. What is the best approach?
This is a clinical table which has to get the Unit Station Description from a second table.
I am new to Oracle so if someone could describe the steps needed for me that would be great.

Answer 1

You should join these two tables
And you should add primary key constraint for the primary table, and foreign key constraint to the second table referencing to first table's primary key column
Look at this basic example
SQL> create table tab1 (id number, desc_id number);
Table created.
SQL> insert into tab1 values(1,1);
1 row created.
SQL> insert into tab1 values(1,2);
1 row created.
SQL>  create table tab2_description (desc_id number, description varchar2(10));
Table created.
SQL> insert into tab2_description values(1,'one');
1 row created.
SQL> insert  into tab2_description values(2,'two');
1 row created.
SQL> select tab1.id tab1_id,  tab2_description.description tab2_desc from tab1, tab2_description
  2  where tab1.desc_id=tab2_description.desc_id;
   TAB1_ID TAB2_DESC
         1 one
         1 two
SQL>- - - - - - - - - - - - - - - - - - - - -
Kamran Agayev A. (10g OCP)
http://kamranagayev.wordpress.com