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What are database normal forms and can you give examples? [closed]
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I've never had a good memory for exact wording, but in my database class I think the professor always said something like:
The data depends on the key [1NF], the whole key [2NF] and nothing but the key [3NF].
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Does Foreign Key improve query performance?
... "Foreign Keys are a relational integrity tool" -- please use the word 'relational' with care. Foreign keys are a database concept, a short hand for a referential integrity constraint. They are not part of the relational model. I assume you made a typo.
– onedaywhen
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What is a Maven artifact?
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@davidblaine - not exactly, that sentence uses the word a more general sense.
– Ken Liu
Apr 17 '13 at 3:35
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Performance optimization strategies of last resort [closed]
...ring out things that the programmer knows are fairly predictable. In other words, don't "interpret" the sequence of things to do, "compile" it.
That redesign is done, shrinking the source code by a factor of 4, and the time is reduced to 10 seconds.
Now, because it's getting so quick, it's hard ...
get and set in TypeScript
...cular, for those not familiar with it, note that you don't incorporate the word 'get' into a call to a getter (and similarly for setters):
var myBar = myFoo.getBar(); // wrong
var myBar = myFoo.get('bar'); // wrong
You should simply do this:
var myBar = myFoo.bar; // correct (get)
myFoo.b...
Meaning of “[: too many arguments” error from if [] (square brackets)
...tcut for the test command), then the string may be split out into multiple words. Each of these is treated as a separate argument.
So that one variable is split out into many arguments:
VARIABLE=$(/some/command);
# returns "hello world"
if [ $VARIABLE == 0 ]; then
# fails as if you wrote:
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How do you get git to always pull from a specific branch?
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+1 for knowing the magic word "refs/heads/master". I had no trouble figuring out how to set the variable, but had absolutely no clue what to set it to, and the man pages weren't much help. I eventually found the right place in the docs after I foun...
How do I get a div to float to the bottom of its container?
...onger participates in the layout of the containing element, so there is no word wrap and the text in the bottom corner is obscured.
– Stephen Martin
Nov 23 '08 at 2:07
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What is “export default” in javascript?
...t would be nice to see an example with default and named exports. In other words, such export which would satisfy import foo, { bar, baz } from './foo';
– gumkins
Apr 27 '17 at 21:34
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When is each sorting algorithm used? [closed]
...iate array and it is stable obviously.
/**
* Some VMs reserve some header words in an array.
* Attempts to allocate larger arrays may result in
* OutOfMemoryError: Requested array size exceeds VM limit
*/
private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
(even though it actually wi...