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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...ly, which has some unexpected side effects:
A new auto-increment ID is allocated.
Dependent rows with foreign keys may be deleted (if you use cascading foreign keys) or else prevent the REPLACE.
Triggers that fire on DELETE are executed unnecessarily.
Side effects are propagated to replicas too....
How to convert NSDate into unix timestamp iphone sdk?
...TimeStamp
{
NSDateFormatter *objDateformat = [[NSDateFormatter alloc] init];
[objDateformat setDateFormat:@"yyyy-MM-dd"];
NSString *strTime = [objDateformat stringFromDate:[NSDate date]];
NSString *strUTCTime = [self GetUTCDateTimeFromLocalTime:strTime];//Yo...
The Definitive C Book Guide and List
...uctures in C, such as lists, sets, exceptions, string manipulation, memory allocators, and more. Basically, Hanson took all the code he'd written as part of building Icon and lcc and pulled out the best bits in a form that other people could reuse for their own projects. It's a model of good C progr...
Why does JQuery have dollar signs everywhere?
...hrough the V8 JS engine (or other engines) and we don't know how much it's allocating for different things.
– Garrett Smith
Jan 1 '18 at 21:24
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Why is Node.js single threaded? [closed]
... @Pacerier I never said that a new thread is spawn, but each thread is allocated to one request until the request is finished.
– Kazaag
Feb 23 '17 at 12:35
2
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Remove duplicate elements from array in Ruby
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If you care about memory, to_set will allocate 4 objects, while uniq allocates one.
– Jan Klimo
Jul 2 '19 at 5:48
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What is the difference between native code, machine code and assembly code?
...erence is that managed code “manages” the resources (mostly the memory allocation) for you by employing garbage collection and by keeping references to objects opaque. Unmanaged code is the kind of code that requires you to manually allocate and de-allocate memory, sometimes causing memory leaks...
How much faster is C++ than C#?
...d expect to get representative results (eg. performing thousands of memory allocations in C++ is going to give you terrible numbers.)
Instead, I wrote slightly more idiomatic C++ code and compared against the C# code @Wiory provided. The two major changes I made to the C++ code were:
1) used vect...
How does PHP 'foreach' actually work?
...ns is that 'FYFY' has the same hash as the removed element 'EzFY', and the allocator happens to reuse the same memory location to store the element. So foreach ends up directly jumping to the newly inserted element, thus short-cutting the loop.
Substituting the iterated entity during the loop
One ...
Where to store global constants in an iOS application?
...0 times and will only create it once. @"foo" is not the same as [[NSString alloc] initWithCString:"foo"].
– Abhi Beckert
Jul 19 '13 at 14:17
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