Help, question about Oracle count distinct 1

[pandatime]

Hi,

I am not an Oracle person (anymore) and I need help with this question, please

If you do:

SELECT COUNT (UNIQUE id) FROM myTable

are the NULL id's counted also??? That is, if you have
id = 1, two id's = 2, and several id's is null, the COUNT would be 3?

Thank you!!

 

[Dagon]

No.

SQL> create table a (a number);

Table created.

SQL> insert into a values (1);

1 row created.

SQL> insert into a values (null);

1 row created.

SQL> select count(distinct a) from a;

COUNT(DISTINCTA)
----------------
               1

Retired (not by choice) Oracle contractor.