Storing a list of codes into a variable in Oracle SQL

Question

There's a way to store a set of codes into a variable in Oracle SQL ?

I have these codes and I'll need to use them in different parts of my query.

But I wouldn't repeat this list in many places in my SQL code.

'G31', 'G310', 'G311', 'G312', 'G318', 'G319', 'G239', 'G122', 'G710',
     'B20', 'B22', 'B23', 'B24', 'G35', 'C811', 'G37', 'G375', 'K702', 'K741'

I would like to do something like this idea:

LIST <- ['G31', 'G310', 'G311', 'G312', 'G318', 'G319', 'G239', 'G122', 'G710',
         'B20', 'B22', 'B23', 'B24', 'G35', 'C811', 'G37', 'G375', 'K702', 'K741']

SELECT * FROM TABLE_A where COLUMN IN [LIST];

SELECT * FROM TABLE_B where COLUMN IN [LIST];

Answer 1

A fancy approach is this

WITH CODE_VALUES AS 
  ( SELECT DISTINCT COLUMN_VALUE AS CODE_VALUE
      FROM TABLE (sys.dbms_debug_vc2coll ('G31',
                                      'G310',
                                      'G311',
                                      'G312',
                                      'G318',
                                      'G319',
                                      'G239',
                                      'G122',
                                      'G710',
                                      'B20',
                                      'B22',
                                      'B23',
                                      'B24',
                                      'G35',
                                      'C811',
                                      'G37',
                                      'G375',
                                      'K702',
                                      'K741'))
  )
  SELECT *
    FROM CODE_VALUES -- + the rest of your query

You could do the same thing with successive union's against "dual" too

WITH CODE_VALUES AS 
    ( SELECT 'ABC' AS code_value FROM dual UNION 
      SELECT 'CDE' AS code_value FROM dual
    )

If this is going to get used across multiple operational queries it's probably best just to store them in a table.

Answer 2

Create a global temporary table once and add the desired values in the gtt and then use it in query using join .

Benifit of gtt is that you don't have to worry about data maintance. (Delete - insert). Data added in one session/transaction will be visible in that session/transaction only (based on type of gtt that you have created.

Create global temporary table gtt
(Col1 varchar2(10))
On commit preserve row; -- session specific

Insert into gtt
Select 'G31' from dual union all
Select 'G310' from dual union all
...
...
Select 'K741' from dual;

Now, you can use it anywhere in the same session as follows:

SELECT * 
FROM TABLE_A a
Join gtt g on a.COLUMN = g.col1;

SELECT * 
FROM TABLE_B b
Join gtt g on b.COLUMN = g.col1;