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Postgresql aggregate array
...
Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need ...
Get class name of object as string in Swift
...ame as String. Like this:
class Utility{
class func classNameAsString(_ obj: Any) -> String {
//prints more readable results for dictionaries, arrays, Int, etc
return String(describing: type(of: obj))
}
}
Now you can do something like this:
class ClassOne : UIViewCont...
Android ViewPager - Show preview of page on left and right
...em visible
val nextItemVisiblePx = resources.getDimension(R.dimen.viewpager_next_item_visible)
val currentItemHorizontalMarginPx = resources.getDimension(R.dimen.viewpager_current_item_horizontal_margin)
val pageTranslationX = nextItemVisiblePx + currentItemHorizontalMarginPx
val pageTransformer = V...
Download multiple files with a single action
... * Download a list of files.
* @author speedplane
*/
function download_files(files) {
function download_next(i) {
if (i >= files.length) {
return;
}
var a = document.createElement('a');
a.href = files[i].download;
a.target = '_parent';
// Use a.downloa...
How can I detect the touch event of an UIImageView?
...swipeRight.direction = UISwipeGestureRecognizerDirectionRight;
[imgView_ addGestureRecognizer:swipeRight];
[swipeRight release];
UISwipeGestureRecognizer *swipeLeft = [[UISwipeGestureRecognizer alloc]
initWithTarget:self action:@selecto...
Pass complex parameters to [Theory]
... : IEnumerable<object[]>
{
private readonly List<object[]> _data = new List<object[]>
{
new object[] { "hello world", 'w', 6 },
new object[] { "goodnight moon", 'w', -1 }
};
public IEnumerator<object[]> GetEnumerator()
{ return _data.GetEn...
How to properly import a selfsigned certificate into Java keystore that is available to all Java app
...se: System.out.println(System.getProperty("java.home"));
Copy the file JAVA_HOME\lib\security\cacerts to another folder.
In Portecle click File > Open Keystore File
Select the cacerts file
Enter this password: changeit
Click Tools > Import Trusted Certificate
Browse for the file mycertificate....
Entity Framework 6 Code first Default value
...unt} nvarchar(128)
SELECT @var{dropConstraintCount} = name
FROM sys.default_constraints
WHERE parent_object_id = object_id(N'{tableSchema}.[{tablePureName}]')
AND col_name(parent_object_id, parent_column_id) = '{columnName}';
IF @var{dropConstraintCount} IS NOT NULL
EXECUTE('ALTER TABLE {tableSc...
Build tree array from flat array in javascript
...ibrary. It's, as far as I can tell, the fastest solution.
function list_to_tree(list) {
var map = {}, node, roots = [], i;
for (i = 0; i < list.length; i += 1) {
map[list[i].id] = i; // initialize the map
list[i].children = []; // initialize the children
}
for (i = 0; i ...
Objective-C: Property / instance variable in category
...ey;
@implementation MyClass
- (NSString *)test {
NSString *result = objc_getAssociatedObject(self, &MyClassResultKey);
if (result == nil) {
// do a lot of stuff
result = ...;
objc_setAssociatedObject(self, &MyClassResultKey, result, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
...