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Is if(items != null) superfluous before foreach(T item in items)?
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@CodeInChaos: Do you typically find that the speed of enumerating an empty sequence is the performance bottleneck in your program?
– Eric Lippert
Jun 23 '11 at 15:19
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How to keep Maven profiles which are activeByDefault active even if another profile gets activated?
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Because the profile is active automatically when the flag is not there. The profile firstProfile is disabled only if you specify -DskipFirstProfile (eg mvn verify -DskipFirstProfile).
– seanf
Jun 28 '17 at 4:08
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What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
JavaScript function in href vs. onclick
...ut wasn't the question asking about the difference between putting the JS call inline in href versus inline in onclick? Assuming you were going to put it inline for some reason, which should you use? (In practice I would do what you've suggested, but you seem to have skipped over the difference betw...
Difference between numpy.array shape (R, 1) and (R,)
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1. The meaning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, a data bu...
How to replace multiple white spaces with one white space
...on isn't as simple as other posters have made it out to be (and as I originally believed it to be) - because the question isn't quite precise as it needs to be.
There's a difference between "space" and "whitespace". If you only mean spaces, then you should use a regex of " {2,}". If you mean any wh...
How to deal with “java.lang.OutOfMemoryError: Java heap space” error?
...form you are running on. In Windows 32 bit this is around 2GB (not specifically heap but total amount of memory per process). It just happens that Java chooses to make the default smaller (presumably so that the programmer can't create programs that have runaway memory allocation without running int...
Mysql error 1452 - Cannot add or update a child row: a foreign key constraint fails
...d FROM sourcecodes) should help to get rid of those IDs. Or if null is not allowed in sourcecode_id, then remove those rows or add those missing values to the sourcecodes table.
– naXa
Feb 23 '16 at 14:28
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How to make a div 100% height of the browser window
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There are a couple of CSS 3 measurement units called:
Viewport-Percentage (or Viewport-Relative) Lengths
What are Viewport-Percentage Lengths?
From the linked W3 Candidate Recommendation above:
The viewport-percentage lengths are relative to the size of the initial...
Apache Tomcat Not Showing in Eclipse Server Runtime Environments
I have tomcat 5.5 installed, running and verifiable at http://localhost:8080/ . The Tomcat menu option appears in the Eclipse menu bar and I can start and stop Tomcat from there. In Eclipse, it does not show as a Server Runtime Environment in Window - Preferences - Server - Runtime Environments, no...