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Pages -E Emulation Feature


Many of us know about script to upgrade the databases using parallel slave processes since 12c. Adding to that there is executable in $ORACLE_HOME/rdbms/bin called dbupgrade utility which in turn calls out

There is little known feature which is emulation feature you can run with this utility or script. it displays on […]

Oracle 12c Upgrade : Virtual Column with Function Based Index (bug)

Issue: Post 12C upgrade: Oracle Bug – Virtual Column issue

Fix: Set it at session level or system level – fix_control=’16237969:OFF’

Be aware of the virtual column getting created with function based index, which may lead to sub-optimal plans.

In 11g , index is getting picked by the oracle optimizer and going with optimal Plan. […]

Oracle 12.2 New Features : Approximate Query Processing

While sometime ago, I was looking for a database project requirement to process analytical workload. The organisation choice was Oracle and Developers choice was postgres or vertica. But to handle Vertica we do not have that much of data processing actually needed so the final contenders are Oracle and Postgres.

As per licensing guidelines I […]

ORA-28040: No matching authentication protocol Database driver error


Hope you might have already gone through below, just in case if not. All of our developer tools/ETL tools datastage/Informatica etc. are failing with ora-28040 once we upgraded to oracle 12c.

This is due to, As per Oracle, In Oracle 12.1 the default value for the SQLNET.ALLOWED_LOGON_VERSION parameter has been updated to 11. This […]

ANZ Webinar Tour – 2017 – Registrations Open

Hello All,

IAOUG and APACOUC proudly announces ANZ Webinar Tour – 2017.

The 2017 Webinar Tour will be running from July 3rd until August 25th with the participation of over 20 International Speakers that will be presenting over 50 interesting presentations, making it the largest webinar series ever made in the Oracle world!

Registration Links […]

Oracle Sharding : Part 2 – Installating & Configuring Shards

In Previous post of the series, I have written about an overview of Oracle Sharding and its features.

In this post, you will be seeing how to configure oracle shard and what steps are need to be performed.

Over all, I felt its very easy to setup and configurewhen compare to RAC setup. All you […]

Oracle Sharding: Part 1 – Overview

Oracle is releasing a whistle blowing feature in distributed databases (shared nothing architecture) which has been dominated by many other databases in recent years. In upcoming release Oracle 12.2 , the Oracle Sharding feature provides the exact capability of shared nothing architecture with Leader node and shard nodes to distribute the data to nodes […]

Rows in Sort order without order by clause?

I have been asked by one of colleague (Vasu) about a weird issue, that the query returns rows in sort order in one database not in the other database.

Without having much hassle, by running dbms_xplan.display_cursor(‘sql_id’,NULL,’ADVANCED) mode tell’s us the optimizer parameter “_gby_hash_aggregation_enabled” is having different values in each database. Which is mean to perform […]

Oracle 12.2 New Features : Convert Non Partitioned Table to Partitioned Table using ALTER

In earlier versions of Oracle, when one want to convert a table to partition, one must use move or export/import method and rename it.

Now in 12.2 release we can use ALTER table command to convert the table into Partitioned Table. Here is sample command it is from the documentation excerpt,



12.2 New Features : Memory Management at PDB Level

Memory & Guaranteed BufferCache/Shared Pool can be allocated at PDB Level. From the white paper here it is

Well so far I haven’t seen any such need to keep a separate memory settings for each PDB as we […]