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How to create a new database after initally installing oracle database 11g Express Edition?
... Apologies, I just noticed you were using XE. It only permits one instance, did it not prompt you to create the instance when you installed the software? You should have a database with the SID "XE" already created. You should have also set up your passwords for the SYS and SYSTEM users...
What is a singleton in C#?
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A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern in C#" c...
Postgresql: Scripting psql execution with password
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Yep, it's deprecated (and so noted in one of the links). Since it's come up, it's probably also worth noting that the deprecation is hotly contested because it's extremely useful for many people yet can be used in some circumstances without serious security conc...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...pread(tmp, y, z)
## x a b c
## 1 x 1 2 3
## 2 y 3 3 2
Using reshape2:
One of the first steps toward the tidyverse was the reshape2 package.
To get a matrix use acast:
library(reshape2)
acast(tmp, x~y, value.var="z")
## a b c
## x 1 2 3
## y 3 3 2
Or to get a data frame, use dcast, as here...
VBA - how to conditionally skip a for loop iteration
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Indeed, is exactly what I have done :) But still it bugs me I have to wrap stuff in the Else piece. Thanks
– Richard H
Dec 30 '11 at 16:22
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Function overloading by return type?
... to what others are saying, overloading by return type is possible and is done by some modern languages. The usual objection is that in code like
int func();
string func();
int main() { func(); }
you can't tell which func() is being called. This can be resolved in a few ways:
Have a predictab...
Hamcrest compare collections
...ed objects it doesn't matter if the list has more
hasItem Checks just for one object it doesn't matter if the list has more
All of them can receive a list of objects and use equals method for comparation or can be mixed with other matchers like @borjab mentioned:
assertThat(myList , contains(allO...
How to find reason of failed Build without any error or warning
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For anyone who is clueless like me: to use this method you may have to search the contents of the output window. My build errors were being hidden by #pragma warning disable statements and were only visible when I searched 'error' i...
How do I specify different layouts for portrait and landscape orientations?
...es to being able to specify two separate layout xml files for an activity, one for Portrait and one for Landscape. I've not been to find any information on how to do that though. How do I specify for each activity which xml file is it's portrait layout and which is the Landscape layout?
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Unable to update the EntitySet - because it has a DefiningQuery and no element exis
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It usually happens because one of the following reasons:
Entity Set is mapped from Database view
A custom Database query
Database table doesn't have a primary key
After doing so, you may still need to update in the Entity Framework designer (or alt...