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What is the point of the diamond operator () in Java 7?
...de by saving repeated type arguments. In practice, it's just two confusing chars more giving you nothing. Why?
No sane programmer uses raw types in new code. So the compiler could simply assume that by writing no type arguments you want it to infer them.
The diamond operator provides no type infor...
How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...
LINQ to Entities only supports casting EDM primitive or enumeration types with IEntity interface
...i eventually found the solution which was for my extension method to call .Select(e => e as T) where T is the child class and e is the base class.
full details are here:
Create IQueryable<T> extension using base class in EF
...
Where to place the 'assets' folder in Android Studio?
...
Select the app folder and then:
File > New > folder > assets Folder ,
the default location is inside /main folder
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...
Parallel foreach with asynchronous lambda
...is:
var bag = new ConcurrentBag<object>();
var tasks = myCollection.Select(async item =>
{
// some pre stuff
var response = await GetData(item);
bag.Add(response);
// some post stuff
});
await Task.WhenAll(tasks);
var count = bag.Count;
If you need something more complex, check o...
SQL Server Installation - What is the Installation Media Folder?
... Server 2019 Developer version. Was lost with dialog prompted from step 3 "Select installation media". This Andy Leonard blog helped me: 1. Downloaded installation package from SQL Server downloads. 2. Launch downloaded wizard > Select installation type > Download media 3. Right-click on the d...
How to read if a checkbox is checked in PHP?
...
checkboxes as an array and foreach ($_POST['food'] as $selected_food) to work on checked one is nice, thanks
– bcag2
May 4 at 13:02
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...
MySQL foreign key constraints, cascade delete
...RITY DEFINER
BEGIN
DELETE FROM
`products`
WHERE
`id` IN (
SELECT `products_id`
FROM `categories_products`
WHERE `categories_id` = category_ID
)
;
DELETE FROM `categories`
WHERE `id` = category_ID;
END
You also need to add the following foreign key constraints...
How can I run just the statement my cursor is on in SQL Server Management Studio?
...
Use Ctrl+KU to select a line.
Then use F5 to run it.
Although it only works for single line selection, still I find it quite useful.
Hope it helps!!
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Method overloading in Objective-C?
... @RaheelSadiq It isn't overloading because the method names (In ObjC: 'selectors') are different. Being different, neither one is considered 'overloaded'. If writeToFile:from: were defined twice, with only the parameter types being different, then that would be overloading. As stated though, t...