REFRESHES

Schema Refresh:

Step 1>> check the presteps on source and target

select name from v$database;
select distinct owner from dba_segments where owner like 'owner_name';
select sum(bytes)/1024/1024/1024 from dba_segments  where owner like 'owner_name';
SELECT COUNT(*) FROM DBA_segments  WHERE OWNER='owner_name';
SELECT COUNT(*) FROM DBA_OBJECTS WHERE OWNER='owner_name';
select segment_type,tablespace_name,count(*) from dba_segments where owner='owner_name' group by segment_type,tablespace_name;
Select constraint_type,status,count(*) from dba_constraints where owner='owner_name' group by constraint_type,status;
select owner ,object_type,status, count(*) from dba_objects  where owner='owner_name' group by owner, object_type, status;

Step 2>>

Take the export or backup of schema on both source and target

exp file=exp_xxx.dmp log=exp_xxxx.log  owner=schema_name compress=n consistent=y buffer=10240000

                                      (or)
expdp dumpfile=expdp_xxx.dmp logfile=expdp_xxx.log directory=xxxx schemas=xxxx,xxxx

Step 3>>
Now drop the objects on target:

select 'drop table  schema_name.'||table_name||' cascade constraints;' from dba_tables where owner='schema_name';

select 'drop '||object_type||' schema_name."'||object_name||'";' from dba_objects where owner='schema_name';

if it is 10g

select 'purge table  schema_name.'||table_name||' cascade constraints;' from dba_tables where owner='schema_name';   
select 'purge '||object_type||' schema_name."'||object_name||'" ;' from dba_objects where owner='schema_name';
select 'purge table '||owner||'."'||object_name||'";' FROM dba_RECYCLEBIN where owner='schema_name';

Step 4>>>
Now proceed with import on target:


imp file=exp_xxx.dmp log=exp_xxxx.log  owner=schema_name  consistent=y buffer=10240000 fromuser=xxx touser=xxxx
                                      (or)
impdp dumpfile=expdp_xxx.dmp logfile=expdp_xxx.log directory=xxxx schemas=xxxx,xxxx