- Written by: ilmarkerm
- Category: Blog entry
- Published: August 7, 2014
When cloning pluggable databases Oracle gives you also SNAPSHOT COPY clause to utilize storage system snapshot capabilities to save on storage space. But it works only when datafiles are placed on ACFS, ZFS Appliance over DNFS or Netapp (Oracle Multitenant Pluggable Database Snapshot Cloning: Use Cases and Supported Platforms Doc ID 1597027.1) and you also cannot unplug/drop the source PDB and you also cannot unplug the clone PDB.
Recently I’ve started to like BTRFS (only on test systems!) and it also has builting snapshot capabilities. In this article I’ll try to use BTRFS snapshots to create pluggable database clones. It is not as automated as Oracle builtin snapshots, but possible.
What I have before cloning:
SQL> select name, open_mode, guid from v$pdbs;
NAME OPEN_MODE GUID
------------------------------ ---------- --------------------------------
PDB$SEED READ ONLY FFCDD773320B2767E0432700FA0A06D0
DB1 MOUNTED FFCC6C3F473E124BE0432700FA0A429E
DB2 READ WRITE 000A7D190B3C15A1E0532700FA0A3C10
SQL> alter session set container=db2;
Session altered.
SQL> select round(bytes/1024/1024) mb, file_name from dba_data_files;
MB FILE_NAME
---------- -------------
280 /u01/db2/system01.dbf
690 /u01/db2/sysaux01.dbf
5 /u01/db2/users01.dbf
100 /u01/db2/tdata01.dbf
2048 /u01/db2/tlarge01.dbf
My goal is to clone DB2 to new PDB called DB3. Currently my DB2 is stored under /u01/db2/ that is a dedicated subvolume under BTRFS filesystem /u01. The file system is currently using 21.23GB.
[root@cdbtest u01]# btrfs subvolume list -a -t /u01
ID gen top level path
-- --- --------- ----
256 1543 5 app
281 736 5 app_bak
285 1545 5 data
286 1297 5 data_bak
287 1544 5 db2
289 1333 5 db2_bak
[root@cdbtest u01]# ls -l /u01/db2
total 3198048
-rw-r----- 1 oracle oinstall 723525632 Aug 7 17:40 sysaux01.dbf
-rw-r----- 1 oracle oinstall 293609472 Aug 7 17:42 system01.dbf
-rw-r----- 1 oracle oinstall 104865792 Aug 7 17:21 tdata01.dbf
-rw-r----- 1 oracle oinstall 20979712 Aug 7 16:56 temp01.dbf
-rw-r----- 1 oracle oinstall 2147491840 Aug 7 17:21 tlarge01.dbf
-rw-r----- 1 oracle oinstall 5251072 Aug 7 17:21 users01.dbf
[root@cdbtest u01]# btrfs filesystem df /u01
Data: total=29.01GB, used=21.23GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.00GB, used=124.73MB
Metadata: total=8.00MB, used=0.00
Now, lets start. First need to open DB2 read only and create description XML file from it:
SQL> exec dbms_pdb.describe(pdb_descr_file=>'/u01/db2_pdb.xml');
PL/SQL procedure successfully completed.
And create a BTRFS snapshot under directory /u01/db3
[root@cdbtest u01]# btrfs subvolume snapshot db2 db3
Create a snapshot of 'db2' in './db3'
[root@cdbtest u01]# btrfs filesystem df /u01
Data: total=29.01GB, used=21.23GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.00GB, used=124.75MB
Metadata: total=8.00MB, used=0.00
[root@cdbtest u01]# ls -l
total 8
drwxr-xr-x 1 oracle oinstall 50 Aug 4 11:55 app
drwxr-xr-x 1 oracle oinstall 50 Aug 4 11:55 app_bak
drwxrwxr-x 1 oracle oinstall 60 Aug 5 15:16 data
drwxrwxr-x 1 oracle oinstall 60 Aug 5 15:16 data_bak
drwxr-xr-x 1 oracle oinstall 136 Aug 7 17:53 db2
drwxr-xr-x 1 oracle oinstall 112 Aug 7 15:47 db2_bak
-rw-r--r-- 1 oracle oinstall 6370 Aug 7 17:53 db2_pdb.xml
drwxr-xr-x 1 oracle oinstall 136 Aug 7 17:53 db3
[root@cdbtest u01]# ls -l db3
total 3198048
-rw-r----- 1 oracle oinstall 723525632 Aug 7 17:49 sysaux01.dbf
-rw-r----- 1 oracle oinstall 293609472 Aug 7 17:49 system01.dbf
-rw-r----- 1 oracle oinstall 104865792 Aug 7 17:49 tdata01.dbf
-rw-r----- 1 oracle oinstall 20979712 Aug 7 16:56 temp01.dbf
-rw-r----- 1 oracle oinstall 2147491840 Aug 7 17:49 tlarge01.dbf
-rw-r----- 1 oracle oinstall 5251072 Aug 7 17:49 users01.dbf
I have a snapshot now and no additional space used! 🙂 Lets try to connect it as a new PDB.
SQL> alter session set container=cdb$root;
Session altered.
SQL> create pluggable database db3 using '/u01/db2_pdb.xml' source_file_name_convert=('/u01/db2/','/u01/db3/') nocopy tempfile reuse;
create pluggable database db3 using '/u01/db2_pdb.xml' source_file_name_convert=('/u01/db2/','/u01/db3/') nocopy tempfile reuse
*
ERROR at line 1:
ORA-65122: Pluggable database GUID conflicts with the GUID of an existing container.
Simple plug in does not work, since the database already has a PDB with the same GUID. Create pluggable database command has a AS CLONE clause to generate new GUID and DBID values.
SQL> create pluggable database db3 AS CLONE using '/u01/db2_pdb.xml' source_file_name_convert=('/u01/db2/','/u01/db3/') nocopy tempfile reuse;
Pluggable database created.
SQL> select name, open_mode, guid from v$pdbs;
NAME OPEN_MODE GUID
------------------------------ ---------- --------------------------------
PDB$SEED READ ONLY FFCDD773320B2767E0432700FA0A06D0
DB1 MOUNTED FFCC6C3F473E124BE0432700FA0A429E
DB2 READ ONLY 000A7D190B3C15A1E0532700FA0A3C10
DB3 MOUNTED 000C54AE44352331E0532700FA0AFA69
SQL> alter session set container=db3;
Session altered.
SQL> select name from v$datafile;
NAME
----------------------------------------------------
/u01/data/CDB2/datafile/o1_mf_undotbs1_9xyyw5dc_.dbf
/u01/db3/system01.dbf
/u01/db3/sysaux01.dbf
/u01/db3/users01.dbf
/u01/db3/tdata01.dbf
/u01/db3/tlarge01.dbf
6 rows selected.
Looks good from the DB side (ignore the UNDO datafile, this is CDB undo datafile, since PDB does not have its own). How does the storage usage look?
[root@cdbtest u01]# btrfs filesystem df /u01
Data: total=29.01GB, used=21.23GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.00GB, used=124.87MB
Metadata: total=8.00MB, used=0.00
Still 21.23GB. Lets open both DB2 and DB3 and see what happens.
SQL> alter session set container=cdb$root;
Session altered.
SQL> alter pluggable database db2 close;
Pluggable database altered.
SQL> alter pluggable database db2 open;
Pluggable database altered.
SQL> alter pluggable database db3 open;
Pluggable database altered.
SQL> select name, open_mode, guid from v$pdbs;
NAME OPEN_MODE GUID
------------------------------ ---------- --------------------------------
PDB$SEED READ ONLY FFCDD773320B2767E0432700FA0A06D0
DB1 MOUNTED FFCC6C3F473E124BE0432700FA0A429E
DB2 READ WRITE 000A7D190B3C15A1E0532700FA0A3C10
DB3 READ WRITE 000C54AE44352331E0532700FA0AFA69
[root@cdbtest u01]# btrfs filesystem df /u01
Data: total=29.01GB, used=21.23GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.00GB, used=124.90MB
Metadata: total=8.00MB, used=0.00
Still no additional storage used by the snapshot. I’ll modify some data in DB3 tables, then it must consume additional space.
SQL> alter session set container=db3;
Session altered.
SQL> select count(*) from t1.large;
COUNT(*)
----------
1897686
SQL> desc t1.large
Name Null? Type
----------------------------------------------------- -------- ------------------------------------
OWNER NOT NULL VARCHAR2(128)
OBJECT_NAME NOT NULL VARCHAR2(128)
SUBOBJECT_NAME VARCHAR2(128)
OBJECT_ID NOT NULL NUMBER
DATA_OBJECT_ID NUMBER
OBJECT_TYPE VARCHAR2(23)
CREATED NOT NULL DATE
LAST_DDL_TIME NOT NULL DATE
TIMESTAMP VARCHAR2(19)
STATUS VARCHAR2(7)
TEMPORARY VARCHAR2(1)
GENERATED VARCHAR2(1)
SECONDARY VARCHAR2(1)
NAMESPACE NOT NULL NUMBER
EDITION_NAME VARCHAR2(128)
SHARING VARCHAR2(13)
EDITIONABLE VARCHAR2(1)
ORACLE_MAINTAINED VARCHAR2(1)
SQL> update t1.large set owner = substr(owner, 1, 2);
1897686 rows updated.
SQL> commit;
Commit complete.
SQL> alter system checkpoint;
System altered.
SQL> select round(bytes/1024/1024) mb from dba_segments where owner='T1' and segment_name = 'LARGE';
MB
----------
256
[root@cdbtest u01]# btrfs filesystem df /u01
Data: total=29.01GB, used=21.78GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.00GB, used=130.33MB
Metadata: total=8.00MB, used=0.00
I tried to change every block on that table. Table is 256MB and 21.78-21.23=0.55GB was changed on the disk. Just for a test, lets try the update again (just to see how BTRFS snapshots work a little).
SQL> update t1.large set owner = 'AX';
1897686 rows updated.
SQL> commit;
Commit complete.
SQL> alter system checkpoint;
System altered.
[root@cdbtest u01]# btrfs filesystem df /u01
Data: total=29.01GB, used=22.00GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.00GB, used=132.34MB
Metadata: total=8.00MB, used=0.00
I should have modified the same blocks, but BTRFS used another 0.22GB of disk space. Need to look more into how BTRFS snapshots work. But here you have it, PDB snapshot cloning without restrictions 🙂
- Written by: ilmarkerm
- Category: Blog entry
- Published: July 25, 2014
I started to write this blog post on how 12c gave us new multitenant architecture (pluggable databases) and with that also a new possibility to do database upgrades. But during writing I discovered how catctl.pl can fail the upgrade if you have modified the SQL plus prompt with custom login.sql.
I’m starting with these already created databases:
| SID | Home | Description |
|---|---|---|
| cdb1 | /u01/app/oracle/product/12.1.0.1/db | The initial container with version 12.1.0.1. It is hosting the pluggable database DB1 that contains my application data. |
| cdb2 | /u01/app/oracle/product/12.1.0.2/db | The target container, already pre-created with version 12.1.0.2 |
All of them use Oracle Managed Files (OMF).
The goal of this blog post is to upgrade database DB1 from version 12.1.0.1 to 12.1.0.2 by unplugging it from CDB1 container and plugging it to CDB2 container that is created with version 12.1.0.2.
I have already created an empty container database CDB2 using new Oracle version 12.1.0.2. The upgrade itself is simply unplugging the DB1 database from the old container, plugging it into new container and running the database upgrade scripts on the container database.
sys@cdb1(cdbtest.aws.ee.dom)> alter pluggable database db1 close immediate;
Pluggable database altered.
Elapsed: 00:00:02.05
sys@cdb1(cdbtest.aws.ee.dom)> alter pluggable database db1 unplug into '/u01/data/db1_upgrade.xml';
Pluggable database altered.
Elapsed: 00:00:01.41
[oracle@cdbtest data]$ . oraenv
ORACLE_SID = [cdb1] ? cdb2
The Oracle base remains unchanged with value /u01/app/oracle
[oracle@cdbtest data]$ echo $ORACLE_HOME
/u01/app/oracle/product/12.1.0.2/db
sys@cdb1(cdbtest.aws.ee.dom)> CREATE PLUGGABLE DATABASE db1 USING '/u01/data/db1_upgrade.xml' nocopy tempfile reuse;
Pluggable database created.
Elapsed: 00:00:10.16
sys@cdb1(cdbtest.aws.ee.dom)> alter pluggable database db1 open upgrade;
Warning: PDB altered with errors.
[oracle@cdbtest data]$ cd $ORACLE_HOME/rdbms/admin
[oracle@cdbtest admin]$ $ORACLE_HOME/perl/bin/perl catctl.pl -c 'DB1' catupgrd.sql
... cut
[CONTAINER NAMES]
CDB$ROOT
PDB$SEED
DB1
PDB Inclusion:[DB1] Exclusion:[]
Time: 2s For PDB(s)
Grand Total Time: 2s
LOG FILES: (catupgrd*.log)
Grand Total Upgrade Time: [0d:0h:0m:2s]
Something is wrong, 2 seconds it too fast. Logfile catupgrd0.log reveals one weird error:
sys@cdb2(cdbtest.aws.ee.dom)> sys@cdb2(cdbtest.aws.ee.dom)> ALTER SESSION SET CONTAINER = "0";
ERROR:
ORA-65011: Pluggable database 0 does not exist.
sys@cdb2(cdbtest.aws.ee.dom)> INSERT INTO sys.registry$error VALUES ('SYS', SYSDATE, 'catctl.pl', 'CATPROC', 'Invalid Upgrade on [0] Check catupgrd*.log', 'Invalid Upgrade');
1 row created.
Now that is a weird error, I specified DB1 as PDB name. Lets try again, first with serial execution. First clean up the failed upgrade from last time:
$ sqlplus / as sysdba
SQL> DELETE FROM sys.registry$error;
1 row deleted.
SQL> commit;
Commit complete.
And run catctl.pl again, with -S flag to run in serial.
[oracle@cdbtest ~]$ cd $ORACLE_HOME/rdbms/admin
[oracle@cdbtest admin]$ $ORACLE_HOME/perl/bin/perl catctl.pl -c 'DB1' -S catupgrd.sql
... cut
[CONTAINER NAMES]
CDB$ROOT
PDB$SEED
DB1
PDB Inclusion:[DB1] Exclusion:[]
PDB Serial Inclusion:[DB1] Exclusion:[0]
Running File In Serial Order FileName is catupgrd.sql
...
So, serial execution works. Lets try one more thing… “Bug 17810688 PDB upgrade error running catcon.pl or catctl.pl” this bug is that PDB upgrade fails when sqlplus is not in PATH, so maybe this is some kind of parsing error of sqlplus output that only shows itself, when PDB-s are upgraded? As you saw here, I’m using custom SQLPlus prompt 🙂 So lets remove my custom login.sql and try running upgrade again, in parallel.
[oracle@cdbtest admin]$ echo $SQLPATH
/home/oracle/dbscripts/oracle
[oracle@cdbtest admin]$ mv $SQLPATH/login.sql $SQLPATH/login.sql.bak
[oracle@cdbtest admin]$ pwd
/u01/app/oracle/product/12.1.0.2/db/rdbms/admin
[oracle@cdbtest admin]$ $ORACLE_HOME/perl/bin/perl catctl.pl -c 'DB1' catupgrd.sql
... cut
[CONTAINER NAMES]
CDB$ROOT
PDB$SEED
DB1
PDB Inclusion:[DB1] Exclusion:[]
------------------------------------------------------
Phases [0-73]
Container Lists Inclusion:[DB1] Exclusion:[]
Serial Phase #: 0 Files: 1 Time: 16s DB1
Serial Phase #: 1 Files: 5
So upgrade started to run this time. I’ll cancel it and try to debug further. Could this be because of the custom prompt? I’ll try again and only comment out this time the line that sets the custom prompt (set sqlprompt):
[oracle@cdbtest admin]$ mv $SQLPATH/login.sql.bak $SQLPATH/login.sql
[oracle@cdbtest admin]$ vi $SQLPATH/login.sql
define _editor=vi
set serveroutput on size 1000000
set linesize 100
set pagesize 9999
column plan_plus_exp format a80
column global_name new_value gname
set termout off
define gname=idle
column global_name new_value gname
select lower(user)||'@'||instance_name||'('||host_name||')' global_name from v$instance;
--set sqlprompt '&gname> '
set termout on
column db_unique_name format a20
column database_role format a16
column db_version format a10
column db_status format a8
column db_compatible format a10
column db_version heading VERSION
column db_status heading STATUS
column db_compatible heading COMPATIBLE
select d.db_unique_name, d.database_role, v.version db_version, p.value db_compatible, v.status db_status
from v$database d, v$instance v, v$parameter p where p.name = 'compatible';
[oracle@cdbtest admin]$ sqlplus / as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on Tue Aug 5 15:24:41 2014
Copyright (c) 1982, 2014, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options
DB_UNIQUE_NAME DATABASE_ROLE VERSION COMPATIBLE STATUS
-------------------- ---------------- ---------- ---------- --------
cdb2 PRIMARY 12.1.0.2.0 12.1.0.2.0 OPEN
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options
[oracle@cdbtest admin]$ pwd
/u01/app/oracle/product/12.1.0.2/db/rdbms/admin
[oracle@cdbtest admin]$ $ORACLE_HOME/perl/bin/perl catctl.pl -c 'DB1' catupgrd.sql
... cut
[CONTAINER NAMES]
CDB$ROOT
PDB$SEED
DB1
PDB Inclusion:[DB1] Exclusion:[]
Time: 2s For PDB(s)
Grand Total Time: 2s
LOG FILES: (catupgrd*.log)
Grand Total Upgrade Time: [0d:0h:0m:2s]
Still doesn’t work. Maybe it doesn’t like database information output, I’ll put back the custom prompt and remove the DB information.
[oracle@cdbtest admin]$ cat $SQLPATH/login.sql
define _editor=vi
set serveroutput on size 1000000
set linesize 100
set pagesize 9999
column plan_plus_exp format a80
column global_name new_value gname
set termout off
define gname=idle
column global_name new_value gname
select lower(user)||'@'||instance_name||'('||host_name||')' global_name from v$instance;
set sqlprompt '&gname> '
set termout on
column db_unique_name format a20
column database_role format a16
column db_version format a10
column db_status format a8
column db_compatible format a10
column db_version heading VERSION
column db_status heading STATUS
column db_compatible heading COMPATIBLE
--select d.db_unique_name, d.database_role, v.version db_version, p.value db_compatible, v.status db_status
-- from v$database d, v$instance v, v$parameter p where p.name = 'compatible';
[oracle@cdbtest admin]$ sqlplus / as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on Tue Aug 5 15:28:42 2014
Copyright (c) 1982, 2014, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options
sys@cdb2(cdbtest.aws.ee.dom)> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options
[oracle@cdbtest admin]$ $ORACLE_HOME/perl/bin/perl catctl.pl -c 'DB1' catupgrd.sql
... cut
[CONTAINER NAMES]
CDB$ROOT
PDB$SEED
DB1
PDB Inclusion:[DB1] Exclusion:[]
------------------------------------------------------
Phases [0-73]
Container Lists Inclusion:[DB1] Exclusion:[]
Serial Phase #: 0 Files: 1 Time: 19s DB1
Serial Phase #: 1 Files: 5
... cut
Grand Total Time: 1404s
LOG FILES: (catupgrd*.log)
Grand Total Upgrade Time: [0d:0h:23m:24s]
And it starts upgrading! So if you have custom login.sql for SQLPlus keep an eye for this during upgrades. This is rather strange bug, because I already used catctl.pl with the same login.sql setup to upgrade a non-CDB database to 12.1.0.2.
But back to the DB upgrade… Now the pluggable database upgrade is finished and we can open it:
sys@cdb2(cdbtest.aws.ee.dom)> select name, open_mode from v$pdbs;
NAME OPEN_MODE
------------------------------ ----------
PDB$SEED READ ONLY
DB1 MOUNTED
sys@cdb2(cdbtest.aws.ee.dom)> alter pluggable database db1 open;
Pluggable database altered.
NB! Need to take special care with physical standby databases when going for this upgrade path!
Fre MySQL seminar on 27. august 2014 @ 13:00. Announcement by Oracle User Group Estonia:
Developing modern applications using MySQL.
In this seminar series learn how to best use MySQL for your existing and new development requirements with leading MySQL expert and Oracle Ace Director Ronald Bradford.
These presentations provide a detailed review of the essential lifecycle components for developing a successful software application and offer a checklist for your company to review the design, development, deployment and support of your business applications with MySQL.
The presentations include:
* Effective MySQL Architecture and Design Practices
* Effective Software Development with MySQL
* Effective Web Site Operations
* Upcoming MySQL features for modern applicationsDetailed description about the topics: read here.
More information about Ronald Bradford:
http://ronaldbradford.com/
https://en.wikipedia.org/wiki/Ronald_Bradford
https://apex.oracle.com/pls/apex/f?p=19297:4:::NO:4:P4_ID:1820To attend this event, PLEASE REGISTER!
This event is organized by Oracle User Group Estonia in cooperation with Finnish, Swedish and Latvian user groups.
The event in Tallinn is sponsored by TransferWise.
If you require more information about this event, please contact ouge@ouge.eu
I know it is a little late announcement, but Oracle User Group Estonia is having its first meetup after many years tonight. I’m presenting there “Making MySQL highly available with Oracle Grid Infrastructure”.
More info and registration here: http://www.meetup.com/Oracle-User-Group-Estonia/events/165539962/.
So if anyone is in Tallinn today, then join us!
I’m also speaking at Oracle User Group Norway 2014 Spring conference (3-5 April 2014), topic “Making MySQL highly available with Oracle Grid Infrastructure”. It will be a great conference!
More info here
- Written by: ilmarkerm
- Category: Blog entry
- Published: April 23, 2013
I was looking for PL/SQL examples to use metadata and data filtering in datapump API, but I didn’t find any. So here is one example. It uses table reload_dev_tables to specify what schemas/tables should be exported using data pump and what where clause should be set.
Structure for reload_dev_tables:
Name Null? Type
----------------------------------------- -------- -------------
OWNER NOT NULL VARCHAR2(40)
TABLE_NAME NOT NULL VARCHAR2(40)
IS_FULL NOT NULL NUMBER(1)
FILTER_PREDICATE VARCHAR2(250)
Here is the datapump code itself, tested in 11.2.0.3. This is just a demonstration how to use the datapump API, specifically the metadata and data filters.