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Does a foreign key automatically create an index?
...en two tables - that has nothing to do with an index per se.
But it is a known fact that it makes a lot of sense to index all the columns that are part of any foreign key relationship, because through a FK-relationship, you'll often need to lookup a relating table and extract certain rows based on ...
Understanding Node.js modules: multiple requires return the same object?
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is this last caveat still true now that npm would install A,B, and APP in a flat directory structure? If not, how can a module be set up to cache its results between multiple other modules?
– Michael
Aug 7 '17 at 22:...
What is the significance of #pragma marks? Why do we need #pragma marks?
...wer showing what pragma marks look like (in that menu or wherever they are now) in the new XCode?
– user7804781
Jul 27 '18 at 17:54
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How do you automatically set text box to Uppercase?
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This is not a full solution, since placeholder is now uppercase (which in most cases shouldn't be). There's no other way than using JavaScript.
– tomericco
Mar 22 '16 at 19:05
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How to prevent scrollbar from repositioning web page?
I have a website with center-aligned DIV. Now, some pages need scrolling, some don't. When I move from one type to another, the appearance of a scrollbar moves the page a few pixels to the side. Is there any way to avoid this without explicitly showing the scrollbars on each page?
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Get month name from Date
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It is now possible to do this with the ECMAScript Internationalization API:
const date = new Date(2009, 10, 10); // 2009-11-10
const month = date.toLocaleString('default', { month: 'long' });
console.log(month);
'lon...
Linear Layout and weight in Android
... always read about this funny weight value in the Android documentations.
Now I want to try it for the first time but it isn't working at all.
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Command prompt won't change directory to another drive
...e
if you want to go to your D:\ drive then type this command
cd /d D:\
now your current working directory is D:\ drive so you want go to Java directory under Docs so type below command :
cd Docs\Java
note : d stands for drive
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Javascript - Track mouse position
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Why tracking a value that you know for sure didn't change? I don't understand, unless it is a homework problem. With the event method, you can track every change of these values, then do a 100ms polling elsewhere if you need to handle these values for what...
For i = 0, why is (i += i++) equal to 0?
...ough decomposition of i += i++ to the parts it is made of requires one to know that both += and ++ are not atomic (that is, neither one is a single operation), even if they look like they are. The way these are implemented involve temporary variables, copies of i before the operations take place - o...