dbms_metadata package to extract the schema ddl

Oracle schema / user ddl  via dbms_metadata

SET LONG 10000  TRIMSPOOL ON  LINES 180 HEADING OFF  FEEDBACK OFF PAGES 0  VERIFY OFF
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'PRETTY',TRUE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'SQLTERMINATOR',TRUE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'SEGMENT_ATTRIBUTES',TRUE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'STORAGE',FALSE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'TABLESPACE',TRUE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'SPECIFICATION',TRUE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'BODY',TRUE);
EXEC DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'CONSTRAINTS',TRUE);

SPOOL ANUJ_DDL.SQL
CONNECT SCOTT/TIGER;
SELECT DBMS_METADATA.GET_DDL (OBJECT_TYPE, OBJECT_NAME, USER) FROM USER_OBJECTS ;

from sys account 

SELECT DBMS_METADATA.GET_DDL (OBJECT_TYPE, OBJECT_NAME, owner) FROM dba_OBJECTS
where owner='SCOTT';