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How does the const constructor actually work?
...st constructor creates a "canonicalized" instance.
That is, all constant expressions begin canonicalized, and later these "canonicalized" symbols are used to recognize equivalence of these constants.
Canonicalization:
A process for converting data that has more than one possible representation in...
Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio
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whilst being used with a left join, where the counted object does not exist.
Using COUNT(*) in this case would also render incorrect results, as you would then be counting the total number of results (ie parents) that exist.
Using COUNT([uid]) IS a valid way of counting, and the warning is not...
VBoxManage: error: Failed to create the host-only adapter
I am running vagrant 1.4 and virtual box 4.3 on fedora 17 machine. When I do "vagrant up", I get this error:
32 Answers...
How do I close all open tabs at once?
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:wqa can be simplified to just :xa
– MattK
Jan 12 '11 at 20:42
145
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Changing position of the Dialog on screen android
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You might try using wlp.x and wlp.y fields to explicitly set the location of the dialog on screen. I haven't tried it myself, but it should probably work.
– Aleks G
Feb 27 '12 at 15:40
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Determine distance from the top of a div to top of window with javascript
...the very top of a div to the top of the current screen? I just want the pixel distance to the top of the current screen, not the top of the document. I've tried a few things like .offset() and .offsetHeight , but I just can't wrap my brain around it. Thanks!
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How do you Encrypt and Decrypt a PHP String?
... The order of encryption and authentication is very important! One of the existing answers to this question made this mistake; as do many cryptography libraries written in PHP.
You should avoid implementing your own cryptography, and instead use a secure library written by and reviewed by cryptograp...
How do I create and read a value from cookie?
...d retrieving cookies.
function createCookie(name, value, days) {
var expires;
if (days) {
var date = new Date();
date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
expires = "; expires=" + date.toGMTString();
}
else {
expires = "";
}
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Is there a bash command which counts files?
... I would not use ls, since it creates a child process. log* is expanded by the shell, not ls, so a simple echo would do.
– cdarke
Jul 3 '12 at 9:24
2
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Replacement for “rename” in dplyr
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Could you explain the syntax? That's more important than the command. I'm using rename(TheDataFrame,OldVarName=NewVarName) but I get Error: Unknown variables: NewVarName. and I don't understand why.
– s_a
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