SQL * Plus Copy Utility

Copy tables from one database to another using copy utility.

connect to sql * plus 

command:
copy from scott/oracle@ORCL-
to rajiv/rajiv@ORCL1-
create new_emp1–
using select * from emp;

----------------------------------------
connect to the schema where the table present then  copy the table to another schema  of other Database.

copy to rajiv/rajiv@ORCL1-
create new_emp2–
using select * from emp;
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Description :

The copy command copies data from one Oracle instance to another.   The data is simply copied directly from a source to a target.  The format of the copy command is:

COPY FROM database TO database action -
  destination_table (column_name, column_name...) USING query

The action can include:
 create – If the destination table already exists, copy will report an error, otherwise the table is created and the data is copied. 
replace – If the destination table exists, copy will drop and recreate the table with the newly copied data. Otherwise, it will create the table and populate it with the data. 
insert – If the destination table exists, copy inserts the new rows into the table. Otherwise, copy reports an error and aborts.
append– Inserts the data into the table if it exists, otherwise it will create the table and then insert the data.

Data type Supports: CHAR,DATE,LONG,NUMBER,VARCHAR2 

More Details:

LINK  : http://docs.oracle.com/cd/B19306_01/server.102/b14357/apb.htm

CDB VS PDB [Oracle 12C]

CDB is an acronym for “Container Database” and PDB is an acronym for “Pluggable Database”. I think it will be easier to explain with a metaphor for DBAs. Think of a freight train with many cars up to 250. Each container could be having different contents, with delivery target for different customers and completely packed/sealed independently with customer options but the entire freight is carried by a single engine or carrier at the front. It will be stupid enough to run 250 freight trucks but rather it is efficient to consolidate them into a single freight train. When running independently we will spend on gas, drivers’ expenses and much more complicated to manage them. The freight train is basically the CDB and each car is the PDB.
PDB is fully backward compatible to pre-12.1 database releases. There is nothing different from a developer or application connectivity perspective. Everything stays the same but the PDB will belong to a single CDB. When application connects to the PDB, it will specify the destination PDB via a database service. All home-grown or third party applications typically will have connectivity defined out of the application so it is easier to just change the service name outside of the application code. So all database connectivity should use “database service” rather than using the legacy approach of ORACLE_SID based connectivity. ORACLE_SID ties the application connectivity to a specific database instance and does not give the scalability or high availability. You can have many pluggable databases in 12.1.you can have up to 250 pluggable databases or PDBs within one container database or CDB. It is clear that there is one-to-many relationship between CDB and PDBS.

Move indexes from one Tablespace to another Tablespace

Method 1:


Select ' ALTER INDEX ' || owner || '.'||INDEX_NAME ||' rebuild tablespace [
 new_tablespace_name];' from DBA_indexes
 where index_name in ( select segment_name from
 dba_segments where tablespace_name='USERS')

Method 2:

declare

type vt is table of varchar2(64);
l_in vt;
begin
-- fetching all names to avoid ORA-01555
select index_name 
bulk collect into l_in
from dba_indexes where tablespace_name='<current index tablespace>';

for i in 1..l_in.count loop
execute immediate 'alter index '||l_in(i)||' rebuild tablespace <new index tablespace>';
end loop;
end;
/

"EXP-00091 Exporting questionable statistics" Error

The "EXP-00091 Exporting questionable statistics" error happens when you export table data with its related optimizer statistics, and Oracle cannot verify the currency of these statistics.  When CBO statistics are created/updated with dbms_stats, the time is noted, but it’s always a good idea not to export statistics since they should be recalculated after import.
You can remove the EXP-00091 error by exporting with "statistics="none" or by setting the client character set

(e.g. export NLS_LANG=AMERICAN_AMERICA.WE8ISO8859P1).
The Oracle docs note this on the EXP-00091 error:

EXP-00091 Exporting questionable statistics

Cause: Export was able to export statistics, but the statistics may not be usable  The statistics are questionable because one or more of the following happened during export: 

- A row error occurred, client character set or NCHARSET does not match with the server, a query clause was specified on export,

- Only certain partitions or sub partitions were exported, or a fatal error occurred while processing a table.

Action: To export non-questionable statistics, change the client character set or NCHARSET to match the server, export with no query clause, or export complete tables. 

If desired, import parameters can be supplied so that only non-questionable statistics will be imported, and all questionable statistics will be recalculated.

STEPS TO GENERATE AWR REPORT

Privileges:

STEP-1
Please connect to sys and give these privileges to Scott.
GRANT SELECT ON SYS.V_$DATABASE TO SCOTT;
GRANT SELECT ON SYS.V_$INSTANCE TO SCOTT;
GRANT SELECT ON SYS.DBA_HIST_DATABASE_INSTANCE TO SCOTT;
GRANT SELECT ON SYS.DBA_HIST_SNAPSHOT TO SCOTT;
GRANT ADVISOR TO SCOTT;
GRANT EXECUTE ON SYS.DBMS_WORKLOAD_REPOSITORY TO SCOTT;

STEP-2 :

SET LINES 400
SET PAGES 400
COL BEGIN_INTERVAL_TIME FOR A40
COL END_INTERVAL_TIME FOR A40
Spool d:\awr.txt
SELECT DBID,INSTANCE_NUMBER,SNAP_ID,BEGIN_INTERVAL_TIME,END_INTERVAL_TIME FROM DBA_HIST_SNAPSHOT ORDER BY 5 DESC;
Spool off;
Note: Use above query to get low snap, high snap details. DBID and Instance number

STEP 3:
Query to Generate AWR report:

SELECT OUTPUT FROM TABLE (DBMS_WORKLOAD_REPOSITORY.AWR_REPORT_HTML (DBID,INSTANCE_NUMBER, LOW_SNAP_ID,HIGH_SNAP_ID,8));
Note : Please put all the details which you have got from step :2

Generate the AWR report on HTML format using below query:
Ex:
SET HEADING OFF;
SET FEEDBACK OFF;
SET LINESIZE 1500;
PROMPT GETTING HTML FORMAT REPORT:
SPOOL d:\AWR_REPORT_HTML.HTML;

SELECT OUTPUT FROM TABLE (DBMS_WORKLOAD_REPOSITORY.AWR_REPORT_HTML (1318580148,1,798,800,8));
SPOOL OFF;

METHOD 2:

Also we can run awrrpt.sql which is located in ORACLE_HOME\RDBMS\ADMIN location.

Datapump jobs

Identifying datapump jobs

TTITLE 'Currently Active DataPump Operations'
COL owner_name FORMAT A06 HEADING 'Owner'
COL job_name FORMAT A20 HEADING 'JobName'
COL operation FORMAT A12 HEADING 'Operation'
COL job_mode FORMAT A12 HEADING 'JobMode'
COL state FORMAT A12 HEADING 'State'
COL degree FORMAT 9999 HEADING 'Degr|(Num|Wrkers)'
COL attached_sessions FORMAT 9999 HEADING 'Sess'
SELECT
owner_name
,job_name
,operation
,job_mode
,state
,degree
,attached_sessions
FROM dba_datapump_jobs;

Killing or stopping a running datapump job


The difference between Kill and Stop is simple to explain. When killing a job, you won’t be able to resume or start it again. Also logs and dumpfiles will be removed!
When exporting (or importing), press Ctrl-c to show the datapump prompt and type KILL_JOB or STOP_JOB[=IMMEDIATE]. You will be prompted to confirm if you are sure…
Adding ‘=IMMEDIATE‘ to STOP_JOB will not finish currently running ‘sub-job’ and must be redone when starting it again.

Processing object type DATABASE_EXPORT/SCHEMA/TABLE/TABLE_DATA
[Ctrl-c]
Export> KILL_JOB
..or..
Export> STOP_JOB=IMMEDIATE
Are you sure you wish to stop this job ([yes]/no): yes


Resuming a stopped job

Now we can ATTACH to the job using it as a parameter to the expdp or impdp command, and a lot of gibberish is shown:
> expdp system ATTACH=EXP_FULL


(Re)start the job with START_JOB, use ‘=SKIP_CURRENT‘ if you want to skip the current job. To show progress again, type CONTINUE_CLIENT (Job will be restarted if idle).

Export> START_JOB[=SKIP_CURRENT]
Export> CONTINUE_CLIENT

GENERATE SCRIPT TO CLEAN THE OBJECTS IN A SCHEMA.

set heading off;
set feedback off;
SELECT 'DROP '||object_type||' '|| object_name||  DECODE(object_type,'TABLE',' CASCADE CONSTRAINTS;',';') FROM user_objects ORDER BY object_id DESC;

SELECT 'PURGE RECYCLEBIN;' FROM dual;
SELECT 'PROMPT After cleanup, number of objects remaining in schema' FROM dual;
SELECT 'SELECT COUNT(*) FROM user_objects;' FROM dual;

LOGIN SYSTEM or SYS :

SELECT 'DROP '||object_type||' '|| object_name||  DECODE(object_type,'TABLE',' CASCADE CONSTRAINTS;',';') FROM dba_objects where owner='SCOTT' ORDER BY object_id DESC;

NOTE : Here owner= 'SCOTT' , You can change schema name which you want to clean.