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How to avoid the “divide by zero” error in SQL?
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@Anderson That's not true at all. Are you sure you didn't accidentally use IsNull instead of NullIf? Try it yourself! SELECT Value,1/NullIf(Value,0)FROM(VALUES(0),(5.0),(NULL))x(Value); Unless by "breaks" you mean returns a NULL? You can convert that to ...
UITextField - capture return button event
...terPressed), for: .editingDidEndOnExit)
}
in enterPressed() function put all behaviours you're after
func enterPressed(){
//do something with typed text if needed
textField.resignFirstResponder()
}
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Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
how to restart only certain processes using supervisorctl?
...rvisor.rpcinterface:make_main_rpcinterface
supervisorctl command can be called with a group name:
supervisorctl restart foo:
as well as with multiple process names:
supervisorctl restart foo:cat1 cat2
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Show current state of Jenkins build on GitHub repo
... updated their authorisation workflow now, users no longer specify what to allow, rather applications must request what they require during authorization and the user approve the requested permissions.
– Ian Vaughan
Aug 14 '15 at 10:07
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How can I clone an SQL Server database on the same server in SQL Server 2008 Express?
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Install Microsoft SQL Management Studio, which you can download for free from Microsoft's website:
Version 2008
Microsoft SQL Management Studio 2008 is part of SQL Server 2008 Express with Advanced Services
Version 2012...
what is faster: in_array or isset? [closed]
... value until it finds a match.
Being an opcode, it has less overhead than calling the in_array built-in function.
These can be demonstrated by using an array with values (10,000 in the test below), forcing in_array to do more searching.
isset: 0.009623
in_array: 1.738441
This builds on Jason...
Xcode 4.2 debug doesn't symbolicate stack call
... NSLog(@"CRASH: %@", exception);
NSLog(@"Stack Trace: %@", [exception callStackSymbols]);
// Internal error reporting
}
Next, add the exception handler to your app delegate:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
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Why am I not getting a java.util.ConcurrentModificationException in this example?
... iterator and listIterator
methods are fail-fast: if the list is structurally modified at any
time after the iterator is created, in any way except through the
iterator's own remove or add methods, the iterator will throw a
ConcurrentModificationException.
This check is done in the next() ...
Generic List - moving an item within the list
...ant.
public void Move(int oldIndex, int newIndex)
Underneath it is basically implemented like this.
T item = base[oldIndex];
base.RemoveItem(oldIndex);
base.InsertItem(newIndex, item);
So as you can see the swap method that others have suggested is essentially what the ObservableCollection doe...