最基本的DDL

（1）：

以下是完成一个表的创建并且指定其主键
SQL> create table test_forum_dategroup
  2  (id integer not null,
  3  sub_id integer,
  4  prgm_id integer,
  5  start_date date,
  6  end_date date);

Table created

SQL> select * from test_forum_dategroup
  2  /

                                     ID                                  SUB_ID                                 PRGM_ID START_DATE  END_DATE
--------------------------------------- --------------------------------------- --------------------------------------- ----------- -----------

SQL> alter table test_forum_dategroup
  2  add constraint pk_test_forum primary key(id)
  3  /

Table altered

SQL> desc test_forum_dategroup
Name       Type    Nullable Default Comments
---------- ------- -------- ------- --------
ID         INTEGER                          
SUB_ID     INTEGER Y                        
PRGM_ID    INTEGER Y                        
START_DATE DATE    Y                        
END_DATE   DATE    Y                        
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