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How to add a primary key to a MySQL table?
...le as it is written now, which can be a little confusing when doing simple SELECT * ...
– StefanK
Apr 12 '19 at 6:45
H...
XPath OR operator for different nodes
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If you want to select only one of two nodes with union operator, you can use this solution:
(//bookstore/book/title | //bookstore/city/zipcode/title)[1]
share
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Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
...
How do I disable text selection with CSS or JavaScript? [duplicate]
...
<div
style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;"
unselectable="on"
onselectstart="return false;"
onmousedown="return false;">
Blabla
</div>
...
Bad class file magic or version
... an Android SDK you should specify at which SDK you refer... (In my case I selected Java 7 because I was using this version) But it depends in your case too. Search online for other errors with the same name, you'll find a lot of information
– Marco Acierno
Jan...
Create Test Class in IntelliJ
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Use the menu selection Navigate -> Test, or Ctrl+Shift+T (Shift+⌘+T on Mac). This will go to the existing test class, or offer to generate it for you through a little wizard.
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CSS “and” and “or”
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&& works by stringing-together multiple selectors like-so:
<div class="class1 class2"></div>
div.class1.class2
{
/* foo */
}
Another example:
<input type="radio" class="class1" />
input[type="radio"].class1
{
/* foo */
}
|| works by se...
Notepad++ - How can I replace blank lines [duplicate]
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Press Ctrl+H (Replace)
Select Extended from SearchMode
Put \r\n\r\n in Find What
Put \r\n in ReplaceWith
Click on Replace All
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improve t...
How to move the cursor word by word in the OS X Terminal
...e sequences for you:
Open Terminal preferences (cmd+,);
At Settings tab, select Keyboard and double-click ⌥ ← if it's there, or add it if it's not.
Set the modifier as desired, and type the shortcut key in the box: esc+B, generating the text \033b (you can't type this text manually).
Repeat fo...
Easiest way to upgrade eclipse 3.7 to 4.2 (Juno)
... is basically an "Eclipse without plugins". Run it (on a fresh workspace), select File -> Import -> Installation -> From existing Installation and point the wizard to your existing 3.7 directory. Check "Install latest versions", hit finish.
That will install the latest versions of the plug...