Pitfalls

Database Migration from non-CDB to PDB – Migration with Data Pump

You may have realized that there are a few techniques missing describing how to do a Database Migration from non-CDB to PDB – Migration with Data Pump is one of them. I will explain the most simple approach of going to Single- or Multitenant. It isn’t the coolest – and it isn’t very fast as soon as your database has a significant size. But it is not complex. And it allows you to move even from very old versions directly into an Oracle 19c PDB – regardless of patch levels or source and destination platform.

Database Migration from non-CDB to PDB – Migration with Data Pump

High Level Overview

Endianness change
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Database Migration from non-CDB to PDB – The Minimal Downtime Challenge

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB – The Minimal Downtime Challenge

Database Migration from non-CDB to PDB – The Minimal Downtime Challenge

When we start to look at a migration from non-CDB to PDB for an important system, regardless of migrating on-prem or to the cloud, reducing the downtime is very important. In this blog post I’d like to highlight the different aspects …

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Database Migration from non-CDB to PDB – The Fallback Challenge

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB - The Fallback Challenge

Photo by Sebastian Grochowicz on Unsplash

Database Migration from non-CDB to PDB – The Fallback Challenge

As I work with customers on upgrades and migrations for a very long time, I know how important a proper fallback is.

When you attempt a migration from a non-CDB to PDB, you need to plan …

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Database Migration from non-CDB to PDB – Various Pitfalls

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB - Various Pitfalls

Photo by timJ on Unsplash

Database Migration from non-CDB to PDB – Various Pitfalls

In all the previous blog posts of this series I tried to explain specific pitfalls, and how you can workaround them. This article is meant to collect the “leftovers”, the minor issues and pitfalls which you may not …

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Database Migration from non-CDB to PDB – The Patch Level Pitfall

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB - The Patch Level Pitfall

Photo by Piron Guillaume on Unsplash

Database Migration from non-CDB to PDB – The Patch Level Pitfall

When you consolidate on a larger scale, it is very likely that you have different patch levels in your database environments. But when you attempt to plugin a non-CDB into a CDB, you may see …

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Database Migration from non-CDB to PDB – The Component Pitfall

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB - The Component Pitfall

Photo by Brett Jordan on Unsplash

The Component Pitfall

With component we mean the database component which you can find in DBA_REGISTRY – or CDB_REGISTRY. When Multitenant became available over 5 years ago, a decision had been made to make all options/components mandatory in a container database. This decision had to …

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Database Migration from non-CDB to PDB – The Time Zone Pitfall

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB - The Time Zone Pitfall

Photo by Allef Vinicius on Unsplash

Database Migration from non-CDB to PDB – The Time Zone Pitfall

Interestingly, there is no issue with different time zone settings within a single CDB. Your CDB$ROOT can be on DST V.32 whereas a PDB you plugin can be already on DST V.33. But only

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Database Migration from non-CDB to PDB – The COMPATIBLE pitfall

There are several pitfalls when you plugin a non-CDB into a CDB environment. I’d like to highlight some of them – and show you potential workarounds as well. This is part of a series of blog posts to make your migration from non-CDB to PDB a bit smoother.

Database Migration from non-CDB to PDB - The COMPATIBLE pitfall

Database Migration from non-CDB to PDB – The COMPATIBLE pitfall

When you migrate your non-CDB to PDB, in most cases the COMPATIBLE setting of the non-CDB will be lower than the setting of the receiving CDB. But still in this case you may see warnings. I will explain how to deal with …

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Database Migration from non-CDB to PDB – Typical Plugin Issues and Workarounds

In the previous blog posts I showed different approaches on how to migrate your database on a same Endianness platform into Multitenant. Whether you prefer to upgrade first or plugin first is up to you. I recommend upgrading first as this allows you a seamless fallback. But regardless of which approach you prefer, you may take care on potential pitfalls. Hence, this blog post is about Database Migration from non-CDB to PDB – Typical Plugin Issues and Workarounds. It may not be complete when I publish it and I may extend it later on. Let me know if you have …

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Cloning with Pluggable Databases in Oracle 18c

We had several discussions on the internal mailing lists the other day about cloning with Pluggable Databases in Oracle 18c (or 12.2.0.1). And I blogged about this topic a while ago but realized I may need to refresh this a bit.

Cloning with Pluggable Databases in Oracle 18c

My example from the old blog post still works fine. But I realized that I switched my database into read-only mode. Hence, I like to repeat it and check different options.

Cloning a 12.1 PDB into Oracle 18c

In the source CDB1 I create a fresh PDB first, then open it and create a cloning user with the necessary …

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Some Data Pump issues: DBMS_DATAPUMP Import via NETWORK_LINK fails + STATUS parameter giving bad performance

One of my dear Oracle ACS colleagues (Danke Thomas!) highlighted this issue to me as one of his lead customers hit this pitfall a week ago. .

DBMS_DATAPUMP Import Over NETWORK_LINK fails with ORA-39126 / ORA-31600

Symptoms are:

KUPW$WORKER.CONFIGURE_METADATA_UNLOAD [ESTIMATE_PHASE]
ORA-31600: invalid input value IN ('VIEWS_AS_TABLES/TABLE_DATA') for parameter VALUE in function SET_FILTER

This can be cured with the patch for bug 19501000 –  but this patch can conflict with:Bug 18793246  EXPDP slow showing base object lookup during datapump export causes full table scan per object and therefore may require a merge patchpatch 21253883 is the one to …

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