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How to get temporary folder for current user
...unction checks for the existence of environment variables in the following order and uses the first path found:
The path specified by the TMP environment variable.
The path specified by the TEMP environment variable.
The path specified by the USERPROFILE environment variable.
The Windows directory....
Difference between EXISTS and IN in SQL?
... will tell you whether a query returned any results. e.g.:
SELECT *
FROM Orders o
WHERE EXISTS (
SELECT *
FROM Products p
WHERE p.ProductNumber = o.ProductNumber)
IN is used to compare one value to several, and can use literal values, like this:
SELECT *
FROM Orders
WHERE Produ...
Left Align Cells in UICollectionView
...CGFloat maxY = -1.0f;
//this loop assumes attributes are in IndexPath order
for (UICollectionViewLayoutAttributes *attribute in attributes) {
if (attribute.frame.origin.y >= maxY) {
leftMargin = self.sectionInset.left;
}
attribute.frame = CGRectMake(l...
Convert nested Python dict to object?
...
Can we guarantee that the order of the list returned by keys() and values() match in order? I mean, if it is a OrderedDict, yes. But a standard dict? I know that CPython 3.6+ and PyPy "compact" dicts are ordered, but quoting documentation: "The order-...
What's the fastest way to merge/join data.frames in R?
...- data.frame(d1, g1, g2)
library(rbenchmark)
benchmark(replications = 1, order = "elapsed",
merge = merge(d1, d2),
plyr = join(d1, d2),
data.table = {
dt1 <- data.table(d1, key = "x")
dt2 <- data.table(d2, key = "x")
data.frame( dt1[dt2,list(x,y1,y2=dt2$y2)] )
...
Multiple left-hand assignment with JavaScript
...bles var2, var3 are becoming globals
Javascript treats this code in this order:
/*
var 1 is local to the particular scope because of var keyword
var2 and var3 will become globals because they've used without var keyword
*/
var var1; //only variable declarations will be hoisted.
var1= var2= va...
Correct way to populate an Array with a Range in Ruby
... if the array is already created and you want to add a range to it: I have order = 1. Then order << (2.25).to_a. But this creates another array inside the array, I simply want the range from 2 to 25. Yet if I try order << (2.25) I get the error can't convert Range into Integer.
...
SQL Server: Get table primary key using sql query [duplicate]
...NSTRAINT_NAME = KU.CONSTRAINT_NAME
AND KU.table_name='YourTableName'
ORDER BY
KU.TABLE_NAME
,KU.ORDINAL_POSITION
;
I have tested this on SQL Server 2003/2005
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Using Auto Layout in UITableView for dynamic cell layouts & variable row heights
...ll to grow in height. (Of course, you need to get the constraints right in order for this to work correctly!)
Getting your constraints right is definitely the hardest and most important part of getting dynamic cell heights working with Auto Layout. If you make a mistake here, it could prevent every...
Throttling method calls to M requests in N seconds
...happen in big bursts by keeping the size M and delay N relatively small in order of handful millis. eg. M = 5, N = 20ms would provide a through put of 250/sec kepping burst to happen in size of 5.
– FUD
Sep 22 '12 at 10:51
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