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What is the difference between save and insert in Mongo DB?
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Save Vs Insert :
In your given examples, the behavior is essentially the same.
save behaves differently if it is passed with an "_id" parameter.
For save, If the document contains _id, it will upsert querying the collection on the _id field, If not, it will insert.
If a document does not...
How to send a command to all panes in tmux?
I like to call :clear-history on panes with a huge scrollback. However, I want to script a way to send this command to all the panes in the various windows.
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What is a “bundle” in an Android application
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Bundles are generally used for passing data between various Android activities. It depends on you what type of values you want to pass, but bundles can hold all types of values and pass them to the new activity.
You can use it like this:
In...
Is there a performance difference between a for loop and a for-each loop?
... iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop ab...
Code Golf: Collatz Conjecture
...sp+0x04], 2
jne .usage
mov ebx, [esp+0x08]
push dword [ebx+0x04]
call atoi
add esp, 4
cmp eax, 0
je .usage
mov ebx, eax
push eax
push msg
.loop:
mov [esp+0x04], ebx
call printf
test ebx, 0x01
jz .even
.odd:
lea ebx, [1+ebx*2+ebx]
jmp .loop
.even:
shr ebx, 1
...
Can we make unsigned byte in Java
...ignedToBytes((byte) -12));
}
Is it what you want to do?
Java does not allow to express 244 as a byte value, as would C. To express positive integers above Byte.MAX_VALUE (127) you have to use an other integer type, like short, int or long.
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How to check if the string is empty?
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s.strip() allocates a new string, which is pure waste. Use string.isspace()
– Clément
Jun 22 at 15:27
add a ...
Locking a file in Python
...terminate in such a way that the lock is left in place and you have to manually delete the lock before the file becomes accessible again. However, that aside, this is still a good solution.
– leetNightshade
Nov 8 '12 at 21:27
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What is time_t ultimately a typedef to?
...IX-compliant systems implement the time_t type as a signed
integer (typically 32 or 64 bits wide)
which represents the number of seconds
since the start of the Unix epoch:
midnight UTC of January 1, 1970 (not
counting leap seconds). Some systems
correctly handle negative time values,
w...
PHP CURL DELETE request
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I finally solved this myself. If anyone else is having this problem, here is my solution:
I created a new method:
public function curl_del($path)
{
$url = $this->__url.$path;
$ch = curl_init();
curl_setopt($ch, CU...