Oracle Database 12c: Invisible columns

Hi everyone,

Today I will talk a little about a new feature on Oracle Database 12c, there are invisible columns. For use this feature there are some restrictions in some types of tables like:
Invisible columns are not supported in external tables, cluster tables, or temporary tables.
Also there are some kinds of operation that will not see a column set to invisible:
A statement with wildcard character, such as select * from mytables.
The SQL*Plus DESC command (Below I will tell how to see invisible columns with DESC command)
A PL/SQL %rowtype declaration
An insert into select * statement

Invisible columns can be made invisible when using thecommands:
create table
create view
alter view
alter table

Lets create a table:

Below we setting the INVISIBLE column with CREATE TABLE command:

SQL> CREATE TABLE TBINVISIBLECL (NAME VARCHAR2(20), SALARY NUMBER(4) INVISIBLE);

Now we are make a invisible column with ALTER TABLE command:

SQL> ALTER TABLE CLIENTS MODIFY (NAME INVISIBLE);

Note:
Making a column invisible will alter the column order in the table.

How to see invible columns with DESC command:

Using our table TBINVISIBLECL created above:

SQL> desc TBINVISIBLECL

Name Null? Type
————————- ——– —————————-
NAME VARCHAR2(20)

Now using the the SET COLINVIBLE ON:

SQL> SET COLINVISIBLE ON
SQL> desc TBINVISIBLECL
Name Null? Type
———————— ——— ——– —————————-
NAME VARCHAR2(20)
SALARY (INVISIBLE) NUMBER(4)

I hope that you enjoy!

Thanks, Felipe!