Cannot create table. SQL Error 02270
<p>This is the table I am trying to create. However, I get the error </p>

<blockquote>
  <p>SQL Error: ORA-02270: no matching unique or primary key for this column-list</p>
</blockquote>

<p>SQL:</p>

<pre><code>create table Meets_In
(
    cid char(20),
    rno integer,
    time char(20),
    CONSTRAINT PRIM_KEY PRIMARY KEY(time),
    constraint meets_fk1 foreign key(cid) references COURSES(CID),
    constraint meets_fk2 foreign key(rno) references ROOMS(RNO)
); 
</code></pre>

<p>These are the parent tables:</p>

<pre><code>create table Courses
(
    cid char(20),
    cname char(20),
    credits integer,
    constraint CoursesKey Primary Key (cid, cname)
);

CREATE TABLE ROOMS 
(
    rno INTEGER,
    address CHAR(20),
    capacity INTEGER,
    CONSTRAINT room_key PRIMARY KEY(rno)
);
</code></pre>

<p>I don't understand why I am getting this error.</p>