Stats Collection Time Anomaly

Johnathan Lewis (@JLOracle) recently published a short post about Stats Collection Time, talking about the table dba_optstat_operation (and dba_optstat_operation_tasks ), which reminded me about (what I regard as) an anomaly in the output in the NOTES columns in Oracle 12C.

I won’t repeat why it’s useful to check these tables as Johnathans note and @MDWidlakes’s comment here should give you all you need to know.

The DBA_OPTSTAT_OPERATION.NOTES column contains the (more...)

DOAG Conference + Exhibition

Another quick post to let you know I will be presenting at the German Oracle User Group Conference [DOAG], which runs from 14th-18th of November 2016

This is a huge conference and exhibition over 4 days with many DOAG_2016tracks and a vast array of great speakers.

I hope to see you in Nuremberg! It will be good. Oh, yes. Es wird gut sein

 

DOAG Konferenz + Ausstellung 2016


Filed under: Administration, Appearances (more...)

POUG 2-day event

Just a quick post to let you know I will be speaking, with a lot of other Oracle ACE and other excellent speakers at the Pint with/Polish Oracle User Group (Chapter IV), taking place on 7th/8th October in Warsaw. Click on Buy Ticket link to see some of the other speakers, or look at the images below.

Hope to see you there! Should be fabulous.

 

poug_speakers_1poug_speakers_2


Filed under: Administration, Appearances Tagged: group, (more...)

Accessing STATUS columns efficiently

A frequently reoccuring design problem with relational databases is the issue locating unprocessed rows in a large table, so we know which rows of data are still yet to be processed.

The problem with a STATUS column is that it generally has low cardinality; there are probably only a handful of distinct values [(C)omplete, (E)rror, (U)nprocessed or something like that]. Most records will be (C)omplete. This makes STATUS a poor candidate for standard B-Tree indexation. (more...)

Oracle Audit Control part 3 – OS files

Just realized that I wrote a follow-up to Part 2 2 years ago and never posted it! So here’s the stripped-out key facts to round off auditing control a bit more:

Deleting O/S audit files is, like, totally necessary. In Oracle 12C (12.1), they are created by default as AUDIT_SYS_OPERATIONS defaults to TRUE now, so you are going to be filling up your AUDIT_FILE_DEST whether you realized it or not.

[NOTE: In theory, this (more...)

UKOUG Tech16 Call For Papers!

It’s that time of year again. The UKOUG Tech16 conference call for papers went out today.

You want to learn a subject really well? Better than you currently know it? Teach someone about it!

You want to help people avoid the potholes and problems that you hit with your implementation? Tell us about that and we’ll love you!

Hi! My name is Neil, and once I was scared to get up in front of people (more...)

UKOUG RDBMS and RAC-CIA Special Interest Groups

On Thursday 21st April, there is a dual UKOUG Database and RAC, Cloud, Infrastructure and Availability special interest group.

For the first time, this even is being held in the fabulous Northern city of Manchester!

There are a dozen interesting, career-assisting, educational talks from end users, Oracle employees and a number of well known Oracle ACE’s at all levels, including Carl Dudley, Jonathan Lewis, Phil Brown and myself.

I will be talking about how (more...)

Proxy Accounts Tracking

If you are using Proxy accounts to access users, for example as a DBA to do a release to a schema owner, how do you know the login was via proxy instead of directly with the password? This information is handily recorded in the audit, assuming you have audit switched on and use “audit session”.

I would recommend that everyone does this anyway, as it’s a useful tool when troubleshooting connection problems – you can (more...)

Accessing a user when you don’t know the password

There are times that you may need to logon to a database user, probably a schema owner to do a release, but you don’t know the password. You may not be able to (easily) change the password as it could be embedded in application connect strings or worse.

If may not be possible simply to change your session using alter session set current_schema=<schema-to-be-changed>; to auto-prefix all of your selects with the schema, especiually if the (more...)

Killing Sessions

You have a session which is out of control. You decide to kill it. What options are available to you as a DBA?

Assuming you don’t have access to the O/S to be able to use O/S commands to kill the session (using kill -9 in Unix/Linux or orakill in windows to kill the thread within the process – “orakill sid thread”), you probably turn to:

alter system kill session 'sid, serial#, @inst_id' immediate;

(note (more...)