NEXTVAL and CURRVAL Pseudocolumns : Rules

Rules for using NEXTVAL and CURRVAL
You can use NEXTVAL and CURRVAL in the following contexts:

• The SELECT list of a SELECT statement that is not part of a subquery
• The SELECT list of a subquery in an INSERT statement
• The VALUES clause of an INSERT statement
• The SET clause of an UPDATE statement
  
  

  You cannot use NEXTVAL and CURRVAL in the following context:

  
  
• The SELECT list of a view
• A SELECT statement with the DISTINCT keyword
• A SELECT statement with GROUP BY, HAVING, or ORDER BY clause
• A subquery in a SELECT ,DELETE, or UPDATE statement
• The DEFAULT expression in a CREATE TABLE or ALTER TABLE statement