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Can I have multiple primary keys in a single table?
...r example:
CREATE TABLE userdata (
userid INT,
userdataid INT,
info char(200),
primary key (userid, userdataid)
);
Update: Here is a link with a more detailed description of composite primary keys.
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Useless use of cat?
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@randomstring I hear you, but I think it really depends on the use case. When used on the command line one additional cat in the pipe might not be a big deal depending on the data, but when used as a programming environment it can b...
How does the String class override the + operator?
Why in Java you're able to add Strings with the + operator, when String is a class? In the String.java code I did not find any implementation for this operator. Does this concept violate object orientation?
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What's the UIScrollView contentInset property for?
...ntent enough to type into it. With the inset, it is as if the content had extra "BLANK CONTENT" the size of the content inset. Blank text has been "inset" into the real "content" -- that's how I remember the concept.
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Visualizing branch topology in Git
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Might I ask where you got the format string from? Or how on earth you concocted that thing?
– elliotwesoff
Oct 6 '16 at 16:38
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What is the advantage of using REST instead of non-REST HTTP?
... which way round).
I think the caching arguments are wrong, because query strings are generally cached, and besides you don't really need to use them. For example django makes something like this very easy, and I wouldn't say it was REST:
GET /get_article/1/
POST /delete_article/ id=1
Or eve...
What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]
...tf8_general_ci is fine only for Russian and Bulgarian subset of Cyrillic.
Extra letters used in Belarusian, Macedonian, Serbian, and Ukrainian
are sorted not well.
The cost of utf8_unicode_ci is that it is a little bit
slower than utf8_general_ci. But that’s the price you pay for correctness...
Why is the minimalist, example Haskell quicksort not a “true” quicksort?
...implementation of putStrLn works by copying the characters of the argument String into to an output buffer. But when it enters this loop, show has not run yet. Therefore, when it goes to copy the first character from the string, Haskell evaluates the fraction of the show and quicksort calls needed t...
CSS: background image on background color
...e box shadow you can always use a pseudo element for the image without any extra HTML:
.btn{
position: relative;
background-color: #6DB3F2;
}
.btn:before{
content: "";
display: block;
width: 100%;
height: 100%;
position:absolute;
top:0;
left:0;
background-ima...
How to slice an array in Bash
... defaults to
zero, an omitted second index defaults to the size of the string being
sliced.
>>> local a=(0 1 2 3 4 5)
>>> # from the beginning to position 2 (excluded)
>>> echo $(array.slice 0:2 "${a[@]}")
>>> echo $(array.slice :2 "${a[@]}...