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Transportable Tablespace PDB Migration and Local Undo

Transportable Tablespace PDB Migration and Local Undo

Photo by Steve Johnson on Unsplash

Sometimes it is necessary to warn you about known pitfalls to avoid frustration. In this particular case I decided not to blog about it simply because I thought this won’t happen to too many other people. Well, yesterday my good friend Philippe Fierens dropped me a message about an issue he ran into with a Transportable Tablespace PDB Migration and Local Undo. And I immediately knew what caused him trouble – and I regret that I didn’t blog about it (sorry Philippe!). We’ve seen the same problem with a large ExaCC migration project …

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In case you miss DBMS_OPTIM_BUNDLE in 12.2

Strange things happen sometimes. I got alerted by a customer before Christmas about package DBMS_OPTIM_BUNDLE missing after applying a Release Update. I’ve had a conversation with Nigel Bayliss, the Optimizer PM – but Nigel hasn’t heard of such things either. We both investigated but couldn’t reproduce the issue. But after the end-of-the-year holidays I received similar messages from other customers. In case you miss DBMS_OPTIM_BUNDLE in 12.2, then this blog post should help you.

In case you miss DBMS_OPTIM_BUNDLE in 12.2

Photo by Caleb Woods on Unsplash

What is DBMS_OPTIM_BUNDLE?

I blogged about this package in the past already several times:

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RMAN Backup Gives RMAN-06091: No Channel Allocated for Maintenance

RMAN Backup Gives RMAN-06091: No Channel Allocated for MaintenanceI really don’t want to turn this blog into an accumulation of issues and flaws. But as I explained many times before, the blog for me is also a way to dump information I likely will need the sooner or later again.

Recently I blogged about another RMAN issue in Oracle 12.2.0.1 with traces. This was fixed with the July 2018 RU for Oracle 12.2.0.1. But the issue below about which Piero Ferraz from Brazil alerted me (thanks!!!), happens in exactly this RU.

RMAN Backup Gives RMAN-06091: No Channel Allocated for Maintenance

This issue gets introduced with the July …

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Data Pump 12.1.0.2 – Wrong Dump File Version – ORA-39142

Data Pump 12.1.0.2 - Wrong Dump File Version - ORA-39142Again I’ll have to thank my colleague Roland Gräff from the German ACS Support team in Stuttgart for bringing this into our radar. Roland alerted me a week ago about an issue with exports in Oracle 12.1.0.2 only when you are on a certain patch level. I summarize the issue here under Data Pump 12.1.0.2 – Wrong Dump File Version – ORA-39142.

In the below blog post you will learn about the actual issue, where it happens and when, and of course how to workaround it.

When does it happen?

The issue I will describe below happens only with

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Special characters show junk in CLOB columns after upgrade to Oracle 12.2.0.1 with JDBC

Special characters show junk in CLOB columns after upgrade to Oracle 12.2.0.1 with JDBCThanks to my support colleague Roland Graeff who told me about this issue at a customer today. And I consider this a pretty serious issue. It can happen that Special characters show junk in CLOB columns after upgrade to Oracle 12.2.0.1. with JDBC.

This is as bad as it sounds. Roland told me about a case where the application showed weird characters instead of German umlauts (ä, ö, ü, Ä, Ö, Ü) after an upgrade from Oracle Database 12.1.0.2 to 12.2.0.1.

Special characters show junk in CLOB columns after upgrade to Oracle 12.2.0.1 with JDBC

Roland explained to me that …

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MMON unconditional traces in Oracle 12.2.0.1

MMON unconditional traces in Oracle 12.2.0.1I love visiting customers onsite. Last week I visited die Mobiliar in Bern, Switzerland. I received a list of open issues to discuss – which is very good to prepare a visit. And when we all were sitting together there was this “Ah, one final thing”. They have an issue with traces the databases writes every few seconds. As a remedy the DBAs increased the backup interval to remove the traces as otherwise the system would potentially run out of inodes or space. All the traces had the same pattern. And I learned quickly: these are MMON unconditional traces in …

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Additional Info for Adaptive Features Fixes in Oracle 12.1.0.2

Additional Info for Adaptive Features Fixes in Oracle 12.1.0.2I blogged about the Adaptive Features fixes in the past several times. But following some of the comments readers had I believe there’s some additional info for Adaptive Feature Fixes in Oracle 12.1.0.2 necessary.

What happened so far?

We delivered the most important fixes not only for adaptive features but only for dynamic sampling and some other things with the Database Bundle Patch in October 2017 for Oracle Database 12.1.0.2. The fixes got delivered on MS Windows a bit earlier.

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Issue with PDB Archives in Oracle 12.2.0.1 in ASM

There is a fancy new command to unplug a PDB in Oracle Database 12.2.0.1:

ALTER PLUGGABLE DATABASE pdb1 UNPLUG INTO 'pdb1.pdb';

The nice thing with this command differing in the file ending of ‘pdb‘ instead of ‘xml as you used it in Oracle 12.1 (and the ‘xml‘ option is still available of course): Instead of just creating an xml description file it zips everything together into a PDB archive.

SQL> show pdbs

    CON_ID CON_NAME			  OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
	 2 PDB$SEED			  READ ONLY  NO
SQL> create pluggable 
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RMAN Recovery Catalog with July PSU: How to resolve RASCHEMAVER and BASCHEMAVER schema mismatch

Related blog posts:


Thanks to Ah Huat Tan from Amway IT Services for keeping me updated!
Actually as I see that more people who got hit by this issue so I’d consider it to be worth to write about it.

Problem and Analysis

You’d apply the July 2016 PSU or BP. According to the readme you are required to upgrade your RMAN catalog afterwards. The …

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Speed up Upgrade Phase 65 with a new catuposb.sql

Credits to Chris Smids from Proximus in Belgium 🙂 Thanks, Chris!!!


Upgrade to Oracle 12.1.0.2 is slow in phase: #65 ?

You are wondering why phase: #65 of the database upgrade to Oracle Database 12.1.0.2 takes quite a while. You dig down into the catupgrd0.log and recognized this statement taking a while:

dbms_output.put_line('catuposb, update 4 - rows updated ' || rows_updated);
END; -- end of update for system internally generated objs
/

The cause for this issue is buried in the script catuposb.sql hitting stale histograms which did not get refreshed even if you gathered dictionary stats before the upgrade …

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RMAN Catalog Upgrade fails – ORA-02296 – error creating modify_ts_pdbinc_key_not_null

This issue got raised to my via a customer I know for quite a while – all credits go to Andy Kielhorn for digging down into that issue and solving it.

Failed RMAN Catalog Upgrade from 11.2.0.4 to 12.1.0.2

The RMAN catalog upgrade:

SQL> @?/rdbms/admin/dbmsrmansys.sql

$ rman CATALOG rman/xxx@rman01

RMAN> UPGRADE CATALOG; 

RMAN> UPGRADE CATALOG;

failed with the following sequence of error messages:

error creating modify_ts_pdbinc_key_not_null
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-06004: ORACLE error from recovery catalog database: ORA-02296: cannot enable (RMAN.) - null values found

error creating modify_tsatt_pdbinc_key_not_null
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR 
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Query on ALL_SYNONYMS is slow in Oracle Database 12c

A customer (Thanks Stefano!) alerted me on this issue during a workshop and I did some further investigation. Basic headline is:

Query on ALL_SYNONYMS is very slow in Oracle Database 12.1.0.2 compared to 11g.

The workaround for this  21324443: SLOW QUERY IN 12C ON ALL_SYNONYMS. is:

dbms_stats.gather_table_stats('SYS','OBJ$',estimate_percent
=>100, method_opt => 'for columns flags size 1, spare3 size 254, type# size 254');

and I see that at least 8 other customers opened SRs hitting the same issue.
Does the workaround suit you in any way?

The bug had no progress since it was opened. If you are seeking progress …

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Fundamental Oracle flaw revealed??? Really …?

This Infoworld article from Jan 17, 2012  Fundamental Oracle flaw revealed did alert Oracle database customers.Infoworld has raised this issue to Oracle before going public with it. Patches are included in the Jan 2012 CPU and PSU. So again, it’s strongly recommended to apply the Jan 2012 PSU (or CPU if you are just asking for security fixes) to your environments.

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