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Count number of records returned by group by
...his to DISTINCT COUNT() OVER(), and the query performance improved dramatically.
– Joe Aldrich
Sep 20 '17 at 13:33
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show 3 more comments
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Simulator slow-motion animations are now on?
...that if he's using a beta, he could have pressed shift 3 times and accidentally activated it?
– CodaFi
Dec 25 '11 at 7:44
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What is a memory fence?
...ead/writes occur in the order you expect. For example a 'full fence' means all read/writes before the fence are comitted before those after the fence.
Note memory fences are a hardware concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemen...
What do the return values of node.js process.memoryUsage() stand for?
... Scheme first.
A running program is always represented through some space allocated in memory. This space is called Resident Set. V8 uses a scheme similar to the Java Virtual Machine and divides the memory into segments:
Code: the actual code being executed
Stack: contains all value types (prim...
How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
...
What exactly is Python's file.flush() doing?
...
There's typically two levels of buffering involved:
Internal buffers
Operating system buffers
The internal buffers are buffers created by the runtime/library/language that you're programming against and is meant to speed things up by ...
What is the difference between pip and conda?
...now pip is a package manager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
...
Saving timestamp in mysql table using php
...But when I pass the timestamp ( 1299762201428 ) to the record, it automatically saves the value 0000-00-00 00:00:00 into that table.
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What's the difference between Thread start() and Runnable run()
...ent the Runnable interface and thus implement the run() method. When you call r1.run() you are executing it in the current thread.
Second example: Two separate threads.
Thread t1 = new Thread(r1);
Thread t2 = new Thread(r2);
t1 and t2 are objects of the class Thread. When you call t1.start(), ...
Throwing the fattest people off of an overloaded airplane.
...ngers)
{
if (totalWeight < targetTotal)
{
// unconditionally add this passenger
myHeap.Add(pass);
totalWeight += pass.Weight;
}
else if (pass.Weight > myHeap.Peek().Weight)
{
// If this passenger is heavier than the lightest
// passen...