Tuesday, May 28, 2019

Oracle 19c - Automation and Manageability Enhancements

Introduction
DBAs should always aim to automate their tasks and avoid as much as possible manual repetitive tasks. This was always true; however, not always implemented; now with the new DevOps era, I see more and more Database teams who have been "hit" by the DevOps trend which demands more automation and collaboration in order to accelerate application updates & delivery

DBCA Silent Mode 
One of the common and popular ways to achieve automation when it comes to installation, configuration, and patching, is to leverage Oracle DBCA (Database Configuration Assistant) tool with the silent mode which is basically and alternative to the regular "GUI" mode DBCA.
When using silent mode, customers can run scripts that will handle a require operation without manual process which requires the "traditional" GUI mode.

Oracle 19c - Automation and Manageability Enhancements
The recent Oracle 19c release has introduced several interesting enhancements in the area of the DBCA silent mode. Now, the following operations can be used with the Silent mode:

Sunday, May 12, 2019

Oracle 19c New Features - Automatic flashback standby database when Primary database is flashed back

Prior to Oracle 19c, when using the "Flashback Database" feature on a primary database in a data guard environment would result in a standby database which is no longer in sync with the primary database; in previous releases, in order to ensure both primary and secondary are synced, then a manual procedure to flash back to standby database was required.

Starting with Oracle 19c, a standby database that is in a mounted state can automatically follow the primary database after a RESETLOGS operation on the primary. This simplifies standby management after a RESETLOGS operation on the primary.

This process is handled by the MRP (Managed Recovery Process) process that will automatically do the work for us.

For more information, see: https://docs.oracle.com/en/database/oracle/oracle-database/19/sbydb/managing-oracle-data-guard-physical-standby-databases.html#GUID-252097AC-3070-43B6-88D8-919AE27F97AD

Oracle 19c Privilege Analysis - Positive Licensing Update!

Introduction

One of the most valuable security related features which have been introduced recently (in Oracle 12c to be specific) is the Privilege Analysis feature. Using this feature, the DBA can easily understand which privileges are actually being used by users. Once the analysis has been completed, the DBA can revoke all of the unnecessary privileges/roles.
I actually wrote a dedicated blog post about this topic with some code examples. See: http://oracledbpro.blogspot.com/2015/12/oracle-12c-privilege-analysis.html

Oracle Database 19c Positive Licensing Update!
Prior to version 19c, this extremely helpful and useful feature was only available for Enterprise Edition with Oracle Database Vault (extra cost option).
Starting from 19c this feature is available with Enterprise Edition; in other words, no need for the data vault option which, is mentioned previously, is an extra cost option.

This is a really nice update from Oracle - let's hope that one day the Diagnostics & Tuning pack features (e.g. AWR, ADDM, ASH, etc.) will be included with the Enterprise Edition without forcing customers to buy the extra cost diagnostics & tuning packs options :)

Reference
https://docs.oracle.com/en/database/oracle/oracle-database/19/newft/new-features.html#GUID-57C5AD70-55F2-4E4E-879A-B2D88A237A24

Saturday, May 11, 2019

Oracle RAC with Standard Edition (SE) 2 is not supported in 19c

Introduction
For so many years (starting in the early 2000's, when 10g was released) Oracle RAC option (Real Application Clusters) was available with Oracle Standard Editions; even when Oracle introduced Oracle Standard Edition 2 (SE2) back in version 12.1.0.2 (see my blog post about SE2 here), they offered the RAC option.

19c Update
With the introduction of the recent 19c release, Oracle did a pretty significant change with SE2 which I believe is worthy of a blog post.
Oracle RAC has been de-supported effective with Oracle Database 19c.
According to Oracle, "SE2 Socket requirements are hard to meet as hardware evolves." In addition, they claim that "SE Oracle RAC has seen diminishing demand with increased high availability requirements, as SE does not provide the full set of high availability capabilities available in the Oracle Database Enterprise Edition".

My Own View
I personally feel like Oracle licensing is too strict and with this recent change it became even stricter. For example, I always believed that Diagnostics and Tuning packs should have been part of the Enterprise Edition by default. I felt like the move to Standard Edition 2 back in 12.1.0.2 was strict as it was more limited than Standard Edition with the same price. I believe that the recent 19c SE2 change is a (valid) tactic to move people to Oracle cloud. The positive news is that from my experience of working with my customer base, the impact on the market should be very low as it's pretty rare to see customers use SE2 with RAC given the limitations of SE2.


Friday, May 10, 2019

Oracle Database 19c is Live!

I hope that by now most of you already heard the exciting news that Oracle 19c is GA on Linux x86-64 (since 25-Apr-2019) and on Oracle Solaris SPARC 64-bit (since 26-Apr-2019). Other platforms such as Windows, HP UX, IBM AIX, etc. are targeted to be release in Q2CY19 according to Document ID 742060.1 on MOS (My Oracle Support) titled "Release Schedule of Current Database Releases"

Where should I test some of the cool new features and enhancements?
You can access LiveSQL which is a cloud-based, free platform to rung and share SQL and PL/SQL. For more info, see: https://blogs.oracle.com/oracle-database/oracle-database-19c-now-available-on-livesql


Sunday, May 5, 2019

How to mitigate the performance/protection trade-off in Oracle Data Guard - Part 2 (Axxana)

Introduction

In the previous blog post titled "How to mitigate the performance/protection trade-off in Oracle Data Guard"  I reviewed the common performance vs. protection trade-off between the various data protection modes in Data Guard : Maximum performance (default), maximum availability and maximum protection.

In that blog post I mentioned how far syn can be used in order to achieve both performance (due to the smaller network latency between primary and local far sync instance) while allowing for higher data protection as the far sync instance is always synced with the primary database.

The Challenge
As the far sync instance is located in a near location to the primary database (probably the same data center), what happens if the entire data center is down due to an unexpected site disaster?
In that case there is a good chance that some of the transactions are not protected as there is an asynchronous replication between the far sync instance and the standby instance. In other words, even when using Far sync, it's not possible to guarantee RPO-0 (zero data loss).

Optional Solution
One solution that I came across in several Oracle conferences (such as Oracle OpenWorld and IOUG Collaborate) which you may consider is Axxana
Axxana is like an Oracle Database "black box" which provides a protected storage unit with DR capabilities Installed at the production site, the Black Box is designed to withstand a wide variety of extreme conditions that may occur during a disaster.

According to the official Azxxana website: "Axxana’s Phoenix for Oracle Far Sync, supported by Oracle, is a self-contained, physically indestructible solution that houses, protects, and supports the Oracle Far Sync instance from within the primary (production) data center. Because a nearby data center is not needed, the risk of a nearby synchronous site failing (e.g., due to a power outage or downed communication lines) no longer exists. Zero data loss is guaranteed, increasing the probability of successful failover. In addition, because the instance can reside at the primary site, communication lines are a matter of feet instead of miles and network latency is negligible. Given that it easily and cost-effectively resolves the challenges associated with standalone versions of Far Sync, there is simply no good reason to use the Far Sync software on any other platform—or for that matter, to use three data centers. IT leaders owe it to their company and their customers to take advantage of the risk reduction, cost savings, and other opportunities that Phoenix for Oracle Far Sync offers."