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connor_mc_d's picture

From Database 18.3 to 18.5 (on Windows)

Contrary to wild rumours on the internet, it was not a fear of the number 13 that led to a numbering jump from version 12c to version 18c. The jump was part of our new, more flexible release mechanism so that we can get fixes and enhancements to customers on a more frequent and predictable schedule. In a nutshell, smaller bundles of features and fixes, more frequently.

I won’t dwell on that – if you’re unfamiliar with the new strategy, the best place to start is  MOS Note 2285040.1, which has a description and a FAQ. But in terms of (as the saying goes) eating one’s own dog food, I downloaded the 18.5 release update which came out this week, and applied it to my 18.3 installation and I thought I’d share the process.

connor_mc_d's picture

EXPORT not GATHER with DBMS_STATS

Just a short post today on something that came in as a question for the upcoming Office Hours session which I thought could be covered quickly in a blog post without needing a lot of additional discussion for which Office Hours is more suited to.

The question was:

“When I gather statistics using DBMS_STATS, can I just create a statistic table and pass that as a parameter to get the results of the gather”

And the answer simply is “No” Smile but let me clear up the confusion.

khailey's picture

“delayed commit ok initiated” – Aurora MySQL

“delayed commit ok initiated” –  is a thread state in Aurora MySQL which indicates the thread has started the async commit process but is waiting for it to be ack’d. You will not find this thread state in MySQL as  MySQL  does not use our async commit protocal, it is Aurora MySQL specific. This is  usually the genuine commit time of a transaction.

This is a “state” and not a wait.

connor_mc_d's picture

My APEX was fine and then it wasn’t

I got a nasty shock this morning when I fired up my local Application Expression installation.

image

It had been working fine and all of a sudden…just dead. I sounded like all of those family members that as I.T practitioners we have to deal with (and that we’re so sceptical of) when they say: “I didn’t change anything…it just stopped!” Smile

In keeping with the treatment of family members, I then adopted the advice that I normally give them first.

connor_mc_d's picture

2018-what grabbed your attention

Here are the blog posts that you hit on most this year, with the most viewed entry on top. Unsurprisingly it is about the release of 18c, but interestingly the ORA-14758 and the Active Sessions post have come up again from last years list, so it appears they are still common issues for the modern Oracle professional. And of course, it is nice to see that my Openworld Mega-download is helping the community.

Thanks for supporting the blog, and as always, there will be more content next year !

connor_mc_d's picture

Your New Years Resolution

Aligning roughly with the calendar year, based on the Chinese zodiak we’re about to go from the year of the dog to the year of the pig. But for me, in the “Information Technology Zodiak” Smile , 2018 was the year of the hack, just as it was in 2017 and just as it will be for 2019.

I’ve not dedicated much time to keeping a record of all of the high profile breaches this year, but just off the top of my head I can think of:

connor_mc_d's picture

Another day…another "use the right datatype" post

Here’s an interesting little oddity (aka bug) with scalar queries.

We’ll start with a simple working example


SQL> create table t1 ( c1 number );

Table created.

SQL> insert into t1 values (1);

1 row created.

SQL> create table t2 ( c1 int, c2 varchar2(10));

Table created.

SQL>
SQL> insert into t2 values(1,'t1');

1 row created.

SQL> insert into t2 values(1,'t01');

1 row created.

SQL> commit;

Commit complete.

SQL> exec dbms_stats.gather_table_stats('','T1')

PL/SQL procedure successfully completed.

SQL> exec dbms_stats.gather_table_stats('','T2')

PL/SQL procedure successfully completed.

SQL>
SQL>
SQL> select a.c1,
  2    ( select max(b.c2) from t2 b where a.c1 = b.c1 )
  3  from t1 a;

        C1 (SELECTMAX
---------- ----------
         1 t1

1 row selected.

That all seems straightforward:

connor_mc_d's picture

A Christmas Carol

You better watch out,
Let me tell you a fact.
If your SQL has literals,
You’re gonna be hacked.

SQL Injection is comin’ to town

We’ve got a library cache,
It’s memory all linked twice.
But it only works well,
When you’re binding all nice.

SQL Injection is comin’ to town

We know when you’ve been lazy,
And concatenated simple strings.
So just make sure you bind your stuff,
And don’t let the bad guys in.

So… you better watch out,
Let me tell you a fact.
If your SQL has literals,
You’re gonna be hacked.

SQL Injection is comin’ to town

 

Merry Christmas everyone! Smile

connor_mc_d's picture

Your AskTOM Top 10 for 2018

Here we go folks…here are the top 10 most viewed questions in AskTOM this year!

We’ll count them down from 10 to 1

10) Inserting values into a table with ‘&’

Viewed 80,000 times.

First asked in 2012, this actually is not a database issue but a client issue. Many client tools view ampersand as a substitution variable, and this they intercept the execution before the command is sent to the database. Full details here

9) What is a SID, how to change it, how to find out what it is

Viewed 95,000 times.

connor_mc_d's picture

It’s all downhill past 30

Yes, it sounds like a lamentation of the aging process, and from my own experience, it is definitely true that the wheels started falling off for my knees, back and plenty of other body parts once I turned 30. But that is perhaps a legacy of too much alcohol, not eating well in my youth and failing to stretch rather than any particular chronological milestone Smile.

But this post is not about that. This one is about the magical 30 character limit on identifiers that we finally lifted in version 12c. For static SQL, this is obviously a no impact change – you either define your tables and columns with longer names or you don’t, and the static SQL you write reflects that position.

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