Materialized View Refresh ON COMMIT

SQL> create table source_table
  2  as select rownum as source_pk, dbms_random.string('X',15) as col_2, sysdate-1000+rownum as col_3
  3  from dual connect by level < 1001
  4  /

Table created.

SQL> 
SQL> alter table source_table add constraint source_pk primary key (source_pk);

Table altered.

SQL> 
SQL> create materialized view my_mv refresh on commit
  2  as select source_pk as key_col, col_3 as data_col from source_table
  3  /

Materialized view created.

SQL> 
SQL> select count(*) from source_table;

  COUNT(*)
----------
      1000

SQL> select count(*) from my_mv;

  COUNT(*)
----------
      1000