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Multiple INSERT statements vs. single INSERT with multiple VALUES
...rting would be pointless anyway even if it did).
Moreover if a clustered index is added to the table the plan still shows an explicit sort step so it doesn't seem to be sorting at compile time to avoid a sort at run time.
I tried to look at this in a debugger but the public symbols for my versi...
AngularJS : Where to use promises?
...96TnxqKhuA?p=preview
Source:
(for those too lazy to click on the links)
index.html
<head>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.1.5/angular.js"></script>
<script src="app.js"></script>
</head>
<body ng-app="...
Evenly distributing n points on a sphere
...g. Note that above I created an offset of my indices by adding 0.5 to each index. This was just visually appealing to me, but it turns out that the choice of offset matters a lot and is not constant over the interval and can mean getting as much as 8% better accuracy in packing if chosen correctly. ...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...nvenient to have the upper bits zeroed, so you can use a value as an array index (because all regs have to be the same size in an effective address: [rsi + edx] isn't allowed). Of course avoiding false dependencies / partial-register stalls (the other answer) is another major reason.
...
What exactly is a C pointer if not a memory address?
...s a Lisp array, and pointers were implemented as a pair of an array and an index. Because of Lisp's array bounds checking, you could never overflow from one object to another.
– Barmar
Mar 5 '13 at 21:20
...
Big-O for Eight Year Olds? [duplicate]
.... It doesn't matter if the collection has 10 items or 10000; it's still at index (say) 3, so we just jump to location 3 in memory.
O(n): retrieving an element from a linked list. Here, A = 0.5, because on average you''ll have to go through 1/2 of the linked list before you find the element you're lo...
How do you convert a byte array to a hexadecimal string, and vice versa?
...7.
Some further considerations:
I didn't use a second loop variable to index into c, since measurement shows that calculating it from i is cheaper.
Using exactly i < bytes.Length as upper bound of the loop allows the JITter to eliminate bounds checks on bytes[i], so I chose that variant.
Mak...
How does Access-Control-Allow-Origin header work?
...t using this header for POST and GET requests. I had accidently opened the index.html file directly from disk, so the URL the client was accessing on node.js was thought to be cross-domain, while it was simply running on localhost. Accessing via the URL (as one would usually do) "solved" my issue......
var functionName = function() {} vs function functionName() {}
...
(Remember that Array#map passes the entry as the first argument, and the index as the second.)
In both cases, the body of the function is just an expression; the function's return value will automatically be the result of that expression (you don't use an explicit return).
If you're doing more t...
Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?
...ion tutorial shows how branch prediction buffers work. The cache buffer is indexed by the lower portion of the address of the branch instruction. This works well unless two important uncorrelated branches share the same lower bits. In that case, you end-up with aliasing which causes many mispredic...