ORACLE APEX SQL how to count distinct fields

Question

I am trying to insert data into a table where an id from a table isn't distinct however, I get the following error message:

PL/SQL: ORA-02287: sequence number not allowed here. 

What is the best way to get around this?

I have copied the code below;

 INSERT INTO data_quality
    SELECT  QLTY_SEQ.nextval, userid, 'Duplicate ID'
    FROM user
    HAVING COUNT(DISTINCT(userid)) = 1;

Thank You in Advance.

Answer 1

You have more than one issue here: once you fixed the sequence, you will have an error due to the fact that you are applying an HAVING without a GROUP BY . You probably need :

INSERT INTO data_quality
    SELECT  QLTY_SEQ.nextval, userid, 'Duplicate ID'
    FROM
    (
      SELECT userid 
      FROM user
      GROUP BY userid
      HAVING COUNT(DISTINCT(userid)) = 1
    )