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MySQL pagination without double-querying?
... help a lot.
The other way is to use SQL_CALC_FOUND_ROWS clause and then call SELECT FOUND_ROWS(). apart from the fact you have to put the FOUND_ROWS() call afterwards, there is a problem with this: There is a bug in MySQL that this tickles that affects ORDER BY queries making it much slower on lar...
Define global variable in a JavaScript function
...
Yes, as the others have said, you can use var at global scope (outside of all functions) to declare a global variable:
<script>
var yourGlobalVariable;
function foo() {
// ...
}
</script>
Alternately, you can assign to a property on window:
<script>
function foo() {
wi...
Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
...
How to grep (search) committed code in the Git history
...s and the like), you need to do:
git grep <regexp> $(git rev-list --all)
git rev-list --all | xargs git grep <expression> will work if you run into an "Argument list too long" error.
If you want to limit the search to some subtree (for instance, "lib/util"), you will need to pass tha...
Adding minutes to date time in PHP
...
$minutes_to_add = 5;
$time = new DateTime('2011-11-17 05:05');
$time->add(new DateInterval('PT' . $minutes_to_add . 'M'));
$stamp = $time->format('Y-m-d H:i');
The ISO 8601 standard for duration is a string in the form of P...
What is in your .vimrc? [closed]
Vi and Vim allow for really awesome customization, typically stored inside a .vimrc file. Typical features for a programmer would be syntax highlighting, smart indenting and so on.
...
Getting the name of the currently executing method
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Thread.currentThread().getStackTrace() will usually contain the method you’re calling it from but there are pitfalls (see Javadoc):
Some virtual machines may, under some circumstances, omit one or more stack frames from the stack trace. In the extreme case, a virtua...
Inspect attached event handlers for any DOM element
...k= handler or HTML <element onclick="handler"> can be retrieved trivially from the element.onclick property from script or in-debugger.
Event handlers attached using DOM Level 2 Events addEventListener methods and IE's attachEvent cannot currently be retrieved from script at all. DOM Level 3 ...
Replace comma with newline in sed on MacOS?
...line, e.g.
echo "a,b" | sed -e $'s/,/\\\n/g'
Note this will not work on all shells, but will work on the most common ones.
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Python glob multiple filetypes
...out:
import glob
types = ('*.pdf', '*.cpp') # the tuple of file types
files_grabbed = []
for files in types:
files_grabbed.extend(glob.glob(files))
# files_grabbed is the list of pdf and cpp files
Perhaps there is another way, so wait in case someone else comes up with a better answer.
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