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Multiple Updates in MySQL
...has new records then i will end up inserting only the ids and count except all other information. if and only if there is an entry for the id then it should update else it should skip. what shall i do?
– Jayapal Chandran
Aug 30 '10 at 13:30
...
ios app maximum memory budget
...ered your own question: try not to go beyond the 70 Mb limit, however it really depends on many things: what iOS version you're using (not SDK), how many applications running in background, what exact memory you're using etc.
Just avoid the instant memory splashes (e.g. you're using 40 Mb of RAM, a...
How can I get the latest JRE / JDK as a zip file rather than EXE or MSI installer? [closed]
... of JDK from Oracle (for example jdk-7u7-windows-x64.exe)
Download and install 7-Zip (or download 7-Zip portable version if you are not administrator)
With 7-Zip extract all the files from jdk-XuXX-windows-x64.exe into the directory C:\JDK
Execute the following commands in cmd.exe:
cd C:\JDK\.rsrc...
C library function to perform sort
...
qsort() is the function you're looking for. You call it with a pointer to your array of data, the number of elements in that array, the size of each element and a comparison function.
It does its magic and your array is sorted in-place. An example follows:
#include <st...
Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
How to detect user inactivity in Android
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Selects Session Timeout to be 5 mins.
Does some operations on the app. (all in foreground)
Now User bring Myapp to background and starts some other app.
----> Count down timer starts and logs out user after 5 mins
OR user turns the screen OFF.
----> Count down timer starts and logs ou...
Check if all elements in a list are identical
... = next(iterator)
except StopIteration:
return True
return all(first == rest for rest in iterator)
One-liner:
def checkEqual2(iterator):
return len(set(iterator)) <= 1
Also one-liner:
def checkEqual3(lst):
return lst[1:] == lst[:-1]
The difference between the 3 versi...
What are the advantages of NumPy over regular Python lists?
... Python objects, at least 4 bytes per pointer plus 16 bytes for even the smallest Python object (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-pr...
Why use sprintf function in PHP?
...
sprintf has all the formatting capabilities of the original printf which means you can do much more than just inserting variable values in strings.
For instance, specify number format (hex, decimal, octal), number of decimals, padding a...
What's the difference between console.dir and console.log?
... @icedwater: Depends on whether you have the console open when you call console.log or open it later. Yes, really. :-)
– T.J. Crowder
Jun 22 '17 at 17:12
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