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Why does this CSS margin-top style not work?
... form a single margin. Margins that combine this way are said to collapse, and the resulting combined margin is called a collapsed margin.
Adjoining vertical margins collapse [...]
Two margins are adjoining if and only if:
both belong to in-flow block-level boxes that participate...
Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You ne...
Javascript object Vs JSON
I want to understand the basic differences clearly between Javascript object and JSON string.
5 Answers
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Date ticks and rotation in matplotlib
...sn't do anything, plt.gca() does not give you the axes you want to modify, and so plt.xticks, which acts on the current axes, is not going to work.
For an object-oriented approach not using plt.xticks, you can use
plt.setp( axs[1].xaxis.get_majorticklabels(), rotation=70 )
after the two avail_pl...
What's the most efficient way to erase duplicates and sort a vector?
...to take a C++ vector with potentially a lot of elements, erase duplicates, and sort it.
23 Answers
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Xcode 4 and Core Data: How to enable SQL Debugging
I'm working on a universal iOS app and I'd like to see the raw SQL in the logs when I'm debugging. There is some info in this blog post about how to enable raw SQL logging for iOS Core Data development. The given example is for Xcode 3 and it's just not clear to me how to enable this in Xcode 4.
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Typescript: difference between String and string
Does anyone know the difference between String and string in TypeScript? Am I correct in assuming that they ought to be the same?
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What does character set and collation mean exactly?
I can read the MySQL documentation and it's pretty clear. But, how does one decide which character set to use? On what data does collation have an effect?
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Storing JSON in database vs. having a new column for each key
...ing user related data in my table - I have 2 columns - uid (primary key) and a meta column which stores other data about the user in JSON format.
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How do I compare two strings in Perl?
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See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary eq returns true if the left argument is stringwise equal to the right argument.
Binary ne returns true if the left argument is stringwise not equal to the right argument....