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ALTER TABLE to add a composite primary key
I have a table called provider . I have three columns called person , place , thing . There can be duplicate persons, duplicate places, and duplicate things, but there can never be a dupicate person-place-thing combination.
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Spring get current ApplicationContext
...But I avoid creating new ApplicationContextProvider() everytime I need to call the getBean() from the context. What I did was to have static ApplicationContextProvider.getApplicationContext() method. Then, when it is time to need the current app context, I invoke: ApplicationContextProvider appConte...
When should I use semicolons in SQL Server?
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Seems they're basically encouraging use of the semicolon in general, by requiring it before all new statement types that have been introduced in recent years. (MERGE too for example). As mentioned in other answers, in the ANSI standard they a...
What is the best way to dump entire objects to a log in C#?
So for viewing a current object's state at runtime, I really like what the Visual Studio Immediate window gives me. Just doing a simple
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'Contains()' workaround using Linq to Entities?
...sion.Lambda<Func<TEntity, bool>>(body, p));
}
//Optional - to allow static collection:
public static IQueryable<TEntity> WhereIn<TEntity, TValue>
(
this ObjectQuery<TEntity> query,
Expression<Func<TEntity, TValue>> selector,
params TValue[] co...
psql: FATAL: database “” does not exist
... it in the past on other machines but it's giving me some trouble when installing on my macbook. I've installed the application and I ran:
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Why does viewWillAppear not get called when an app comes back from the background?
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In other words, if someone looks at another application or takes a phone call, then switches back to your app which was earlier on backgrounded, your UIViewController which was already visible when you left your app 'doesn't care' so to speak -- as far as it is concerned, it's never disappeared and...
Finding child element of parent pure javascript
...esire.
Edit: Now that I think about it, you could just use querySelectorAll to get decendents of parent having a class name of child1:
children = document.querySelectorAll('.parent .child1');
The difference between qS and qSA is that the latter returns all elements matching the selector, while...
Prototypical inheritance - writing up [duplicate]
...bob and ben
The member walk is part of Person.prototype and is shared for all instances bob and ben are instances of Person so they share the walk member (bob.walk===ben.walk).
bob.walk();ben.walk();
Because walk() could not be found on bob directly JavaScript will look for it in the Person.prot...
R cannot be resolved - Android error
I just downloaded and installed the new Android SDK. I wanted to create a simple application to test drive it.
108 Answers
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