There are 2 PL/SQL packages for performing data mining/predictive analytics in Oracle. The main PL/SQL package is DBMS_DATA_MINING. This package allows you to build data mining models and to apply them to new data. But there is another PL/SQL package.
The DBMS_PREDICTIVE_ANALYTICS package is very different to the DBMS_DATA_MINING package. (more...)
I was looking at the Apex 4.2.2 installation script (coreins.sql), and noticed the mention of a new package, wwv_flow_json, which is apparently being worked on but was removed at the last minute "as no longer required for 4.2.2".
Even though the package is not installed (more...)
Here is a short story about a little problem that caused me a bit of grief; but in the end had a simple cause and a simple fix.
I had a dynamic action in my Apex 4.1 app that had to run some PL/SQL – which was working fine, (more...)
Have you heard of Oracle Designer? Perhaps you even still use it?
Designer incorporates support for business process modeling, systems analysis, software design and system generation.
I don’t want to get you too excited, because this technology is being phased out. You can read the official statement of direction here (more...)
Over the weekend one of my friends asked me for a clarification on RESULT_CACHE
- a really interesting functionality that allows Oracle to cache in SGA results of PL/SQL function calls.
The point of confusion was the fact that between 11gR1 and 11gR2 Oracle development team significantly re-thought this feature (more...)
Yet another performance tuning story
, similar to one that happened about a month ago
. Just to keep it short:
- once upon a time there was a very time-consuming module.
- eventually we were forced to take much closer look - WHY is it so time-consuming
- we found in our own (more...)
After a couple of requests at IOUG Collab'13 I decided to resurrect a pretty old topic that I've participated in 2008 (since in 5 years there was no changes on that front :-) ).
As we all know, starting version 11g Oracle tracks PL/SQL dependencies in much more granular way (more...)
I was looking for PL/SQL examples to use metadata and data filtering in datapump API, but I didn't find any. So here is one example. It uses table reload_dev_tables to specify what schemas/tables should be exported using data pump and what where clause should be set.
Structure for reload_dev_tables:
For the Friday evening I decided to dig out my example from the most recent of my published books (Expert PL/SQL Practices, APress, 2011
) - it was a very fun project to work with: first, to come with with the idea of such multi-author book, second, to write (more...)
SQLTXPLAIN (SQLT) collects diagnostics details about a SQL statement that either performs poorly or it produces unexpected results (also known as wrong results). In addition to that, it also performs over a hundred health-checks around the SQL statement being analyzed. The results of these so called health-checks are displayed on (more...)
create edition allows_one_plsql_object
as child of itself_with_differing_code;
comment on edition allows_one_plsql_object is
'so you can release changes with no dowmtime!';
This post is a continuation of a topic, I've raised previously - dynamic implementation of generic searches
. As I mentioned in that post, there are circumstances, when it is much more convenient to return a pointer to a row-set instead of that row-set. Or in terms of Oracle - REF CURSOR (more...)
It is a very common problem - how do you implement generic search over the table? By generic search I mean that users are provided with tons of different options that could be used in all possible permutations.
It leads to a standard problem - how do you make sure (more...)
With all analytics or data science projects one of the first steps typically involves the extraction of data from various sources, merging the data and then performing various statistics.
The extraction and merging of the data is well covered by lots of other people blogging about how to use Oracle (more...)
I'm busy deriving file layouts from PL/SQL. Probably close to 100 file definitions...each of them slightly different, each of them defined in the code. Fun!
There are a mixture of types too, fixed width, csv, etc. Thankfully, I've read enough of the code now that it's relatively easy to (more...)
Sometimes interesting problems lead to shock or dismay at the suppositions of why they occur. Why an
ORA-22979 is raised is one of those, and the error is typically:
ERROR at line 1:
ORA-22979: cannot INSERT object VIEW REF OR user-defined REF
This error (more...)
Always check out the original article at http://www.oraclequirks.com for latest comments, fixes and updates.
Just a simple reminder (I tend to forget things over the centuries) when using procedure DBMS_LOB.CONVERTTOCLOB with persistent lob locators:
don't forget to include the FOR UPDATE clause in the SELECT statement fetching (more...)
I've just noticed in one of LinkedIn PL/SQL forums the following question:
- Which one is faster and why SELECT 1 FROM DUAL
or SELECT ROWID FROM DUAL
Yes, it's pretty basic question, but it's interesting enough to be covered. The answer is pretty simple - do not use ROWID (more...)
I've been scratching my eyes out lately trying to reverse engineer
lots of PL/SQL.
One thing I've seen a lot of is calls to dbms_output.put_line
. Fortunately, I've seen some dbms_application_info.set_module
and other system calls too. But back to that first one.
1. When I used dbms_output