When solving Kakuro it is essential to know for a given integer X and a given number of elements N all the combinations of N non-repeating digits [1-9] that their sum equals to X.
For example, there is only one combination for creating the number 7 from 3 elements:
And there are 6 combinations for creating the number 15 from 4 elements:
Let’s generate a list of all (more...)
If you've ever used a PL/SQL dynamic action with the default 'wait for result', you would have seen the following warning if you have the browser console open.
|Text for bots: Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience.|
Consider this scenario of dynamic actions on change of P42_ITEM:
|Synchronous vs Asynchronous server calls|
Zwei großartige Hilfsmittel hat Paul Randal
vor wenigen Wochen in seinem Blog bekannt gemacht:
- SQL Server Wait Types Library: eine Liste mit den seit Version 2005 im SQL Server vorkommenden Wait Typen und Erklärungen zu ihrer Bedeutung, ihrer Verfügbarkeit, ihrer Beziehung zu des Extendes Events, sowie Informationen zum Troubleshooting.
- SQL Server Latch Classes Library: mit entsprechenden Informationen zu den Latch Klassen.
Diese Links könnten mir allerlei Suchoperationen in Books Online ersparen.
Sometimes when you present an advanced feature, questions from the audience reveal misconceptions about basic features.
It happens to me almost every time I talk about Edition-Based Redefinition. I present Editioning Views, and then I get questions that reveal misunderstandings about views in general.
One such misunderstanding is regarding what is kept in the view definition.
When we create a view as “select * from table”, the * is expanded to actual (more...)
Last week I had the pleasure of spending a few days in lovely Stowe, Vermont at the Stoweflake Mountain Resort and Spa attending the 3rd Annual World Wide Data Vault Consortium (#WWDVC). Not only was the location picturesque, the weather was near perfect, the beer was tasty, and the learning and networking were outstanding. We had 75 […]
Next question in my 2015 survey
, how many different ways can we all type "chrome"?
Q4: Which browser do you use for development?
The first free text question, with a long variety of unique results. I haven't analysed the complete list to get a truer result, but the pattern is clear. 3 of the top 5 are Chrome. APEX developers build in Chrome, the application builder is recommended for Chrome, especially during early adopter (more...)
Learn how Snowflake automatically optimizes SQL queries. It is all handled “auto-magically” via a dynamic optimization engine in our cloud services layer.
If you’re reading this post, you most likely are trying to run the Oracle Database 11g or 12c
runInstaller program, and it’s failing a critical dependency check and displaying an error like the one below. If so, choose
n because if you choose
y it won’t launch the Oracle Installer.
Starting Oracle Universal Installer...
Checking Temp space: must be greater than 500 MB. Actual 30824 MB Passed
Checking swap space: must be greater than (more...)
Installing any Oracle database is tedious, but the installing the pre-requisites can be tedious. This post tries to simplify the process by creating a single
prereq.sh file for all the pre-requisite libraries. The file should contain the following:
yum install -y binutils \
One of the new features with Oracle database 12c is the new syntax for Top N queries and pagination. Did we really need this? Should you choose for the new syntax over the way we used to do it, with an inline view? I think so, it simply adds syntactic clarity to the query, and in this blogpost I will show the difference between the "old" and the "new".
For the examples I will use (more...)
This post shows you how to add the menu option and GUI to set users and groups. It’s quite a bit easier than mastering all the command-line syntax. It makes setting up the required user and group accounts for an Oracle Enterprise or MySQL database solution much easier.
You add the utility by calling the yum (Yellowdog Updater, Modified) utility like this:
yum installed -y system-config_users
You should see the following:
Consolidation is a key enabler for Oracle database deployments on both public and private clouds. Consolidation reduces the overall IT costs by optimizing the operational and capital expenses. In addition, it enhances the effective utilization of cloud resources. The Exadata database machine has been optimized to run schemas and databases with mixed workloads together, making … Continue reading
Why you might want to think twice about using INSERT ALL.
One of those things I knew and then forgot.
So, let’s say you’ve got three tables or a partitioned table or something like that.
Let’s use regional tables for simplicity.
drop table t1_r1;
drop table t1_r2;
drop table t1_r3;
create table t1_r1
(col1 varchar2(2) not null
,col2 number not null
,check( col1 in ('R1')));
create table t1_r2
(col1 varchar2(2) not null
,col2 number not (more...)
In a recent release that I’ve been working on, we had to drop and recreate some of the unique/primary key constraints (due to columns being added into the constraint) on some of our tables.
Prior to working in this team, I had only ever come across explicitly creating the indexes for a table, similar to:
create table test_explicit_index (col1 number,
create unique index col1_exp_pk on test_explicit_index (col1);
We can see the (more...)
Need help choosing sessions for #KScope16? Here are my Top 5 for the #BigData track
Occasionally, my students loose their network connection when copying their virtual machines. This article shows you how to rebuild your Internet connection.
The first step requires you to identify the port number on your host operating system, which is typically Windows OS or Mac OS X. You can find that by running the following search from a Mac OS X Terminal session or Windows OS Command session.
If you’re on the Mac OS X, you (more...)
The next question in my 2015 survey
was a high level look at what resources developers use to get through your day.
On a slightly side note, there was an interesting discussion on the science of preferred vs effective learning styles in this podcast
. It reminded me of my scuba diving course where we learnt the content using 5 different methods, which was a great way to ensure everyone understood how to survive in a (more...)