Why you should never put objects into the SYSTEM or SYSAUX tablespace

Just because you can doesn’t mean you should

I still see it happening that people put object, i.e. tables, etc. in the SYSTEM or SYSAUX tablespace. Sometimes it’s done deliberately, sometimes it happens automatically by creating a table in the SYS schema. Well, let me tell you, it’s a really bad idea. You should not put any kind of user object into those tablespaces. Even the Oracle Database Documentation warns you of doing so:

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Creating an Oracle Database Docker image

Run your Oracle database inside a Docker container

Oracle_Docker

Oracle has released Docker build files for the Oracle Database on Github. With those build files one can go ahead and build his or her own Docker image for the Oracle Database. If you don’t know what Docker is you should go and check it out. It’s a cool technology based on the Linux containers technology that allows you to containerize your application, whatever that application may be. Naturally, it didn’t take long for people to start looking at containerizing databases as well which makes a lot of sense, especially for, but not only, development and test environments. Here is a detailed blog post on how to containerize your Oracle Database by using those build files that Oracle has provided.

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Oracle 12c R1 background processes

Here is yet another Oracle 12c post to add to all those out there and this one starts with a question: How many background processes exist in an Oracle DB 12.1 environment to date? Just take a moment and take a guess, if you haven’t already seen the bold number coming up. The answer is: 108! That is with all the available bells and whistles turned on but it gives you an idea of how much engineering has gone into the Oracle Database over all those 30+ years. In Oracle 12c there is a total of 19 new background processes meaning that if you are running in an 11gR2 environment you will only have 92. Wait, 92? 108 – 19 = 89 and not 92. Those numbers don’t add up so what happened? It is one of those questions I get these days when talking about 12c. Although you can’t change it anyway people want to know what has changed between the versions and I guess: Fair enough. So there you have it, the reason for this post: To share my little research and perhaps answer the same question from one or two people out there before it reaches me via other channels. Or worst case, a link that I can copy/paste rather than having to type this all over again. Continue reading “Oracle 12c R1 background processes”

Oracle 12c R1 enqueue waits

Just as with the new Oracle 12c R1 lock types it’s time to take a quick look at the new enqueue waits in 12c. Oracle 11.2.0.3 had a total of 304 enqueue waits. 12.1 has a total of 418. A lot of work seems also to have happened on ASM in this release. The amount of new enqueues per group looks as follows:

Group Amount
ASM Enqueue 16
Enqueue-Cross SCN 12
Backup/Restore 11
Queue Ptning global enq 8
Being Written Redo Log 8
SGA Log-Bkt Flush 6
AM Container 5
Media Recovery 5
OLS groups 4
Instance Recovery 3
AVM RTA Access 3
AM Contained File Identification 3
Privilege Capture API 2
Queue table enqueue 2
Label Security Profile 2
RFS Logminer FLC 2
Data Guard Broker 2
IOServer File 2
Queue Partitioning local enqueue 2
Column Key 1
Flush Stat 1
Pluggable Database 1
SGA Log Operation 1
AM Group Rebuild/Validate 1
Real-Time ADDM Flood Control 1
AM Contained File Resize 1
PDB DDL Operations 1
non durable sub bmap alloc 1
CBAC Master Lock 1
IOServer Client 1
PDB Instance State 1
Oracle File System Operation 1
KJCI Serialization Enqueue 1
Spillover Audit files 1
Application Continuity 1
File Set / Dictionary Check 1

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Oracle 12c R1 lock types

As stated in my previous post, it’s time for me to revisit some of my posts and check the relevance for 12c. Let’s start with the one on locks. As posted in late 2010 there are 202 different lock types in Oracle 11g. It’s actually 205 in 11.2.0.3 which was not out back then. Anyway, in 12.1 we have now 240 but still only 4 which are caused by user interaction, aka. SQL statements.

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