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How to wait for several Futures?
...ave several futures and need to wait until either any of them fails or all of them succeed.
8 Answers
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SQL Server - Create a copy of a database table and place it in the same database?
...a new table with the same column structure (just like he said) and inserts all data into the new table for you.
– user5855178
Apr 5 '17 at 14:14
1
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Can comments be used in JSON?
...
No.
The JSON should all be data, and if you include a comment, then it will be data too.
You could have a designated data element called "_comment" (or something) that would be ignored by apps that use the JSON data.
You would probably be bett...
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...
ElasticSearch: Unassigned Shards, how to fix?
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By default, Elasticsearch will re-assign shards to nodes dynamically. However, if you've disabled shard allocation (perhaps you did a rolling restart and forgot to re-enable it), you can re-enable shard allocation.
# v0.90.x and earlier
curl -XPUT 'localhost:9200/_settings' -d '{
"in...
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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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
...
C++ Modules - why were they removed from C++0x? Will they be back later on?
...and classes:
export {
int f(int);
double g(double, int);
int foo;
namespace Calc {
int add(int a, int b);
}
}
void not_exported_function(char* foo);
An important change of modules will be that macros and preprocessor definitions will be local to modules and...
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 ...