title: Oracle 12c, export table with sequence as default value, schema is attached
body: <p>I'm use oracle 12c with a user u1. With user u1 I create table T1 like this,</p>
  
  <pre><code>create SEQUENCE  T1_SEQ START WITH  1;
  CREATE  table T1(
    id number(11) DEFAULT T1_SEQ.nextval PRIMARY KEY ,
    name varchar2(255)
  );
  </code></pre>
  
  <p>Now I want to export the schema to others, and use below command to export </p>
  
  <pre><code>expdp u1/password dumpfile=u1.dmp  schemas=u1
  </code></pre>
  
  <p>, but when others use u1.dmp to import the schema with a new user named u2,</p>
  
  <pre><code>impdp u2/password   remap_schema=u1:u2  DUMPFILE=u1.DMP TABLE_EXISTS_ACTION=REPLACE
  </code></pre>
  
  <p>error happend, beacause default value of table T1 column id add U1 as prefix.</p>
  
  <pre><code>U1.T1_SEQ.nextval
  </code></pre>
  
  <p>and here is the new create table statement</p>
  
  <pre><code>CREATE  table T1(
        id number(11) DEFAULT U1.T1_SEQ.nextval PRIMARY KEY ,
        name varchar2(255)
      );
  </code></pre>
  
  <p>How can I remove the U1's influence while I want to move one schema to  another schema.
  Could you give me some suggestions? Thanks in advance!.</p>