Tutorial by Examples: g

Create Oracle error log table ERR$_EXAMPLE for existing EXAMPLE table: EXECUTE DBMS_ERRLOG.CREATE_ERROR_LOG('EXAMPLE', NULL, NULL, NULL, TRUE); Make writing operation with SQL: insert into EXAMPLE (COL1) values ('example') LOG ERRORS INTO ERR$_EXAMPLE reject limit unlimited;

Query: WITH generator ( value ) AS ( SELECT 1 FROM DUAL UNION ALL SELECT value + 1 FROM generator WHERE value < 10 ) SELECT value FROM generator; Output: VALUE ----- 1 2 3 4 5 6 7 8 9 10

Sample Data: CREATE TABLE table_name ( value VARCHAR2(50) ); INSERT INTO table_name ( value ) VALUES ( 'A,B,C,D,E' ); Query: WITH items ( list, item, lvl ) AS ( SELECT value, REGEXP_SUBSTR( value, '[^,]+', 1, 1 ), 1 FROM table_name UNION ALL SELECT value, ...

we can create a new controller with rails g controller command. $ bin/rails generate controller controller_name The controller generator is expecting parameters in the form of generate controller ControllerName action1 action2. The following creates a Greetings controller with an action of hell...

public class App : Application { internal static NavigationPage NavPage; public App () { // The root page of your application MainPage = new RootPage(); } } public class RootPage : MasterDetailPage { public RootPage() { var menuPage = ne...

You can use re.finditer to iterate over all matches in a string. This gives you (in comparison to re.findall extra information, such as information about the match location in the string (indexes): import re text = 'You can try to find an ant in this string' pattern = 'an?\w' # find 'an' either w...

The Windows API GetTickCount function returns the number of milliseconds since the system (computer) was started. The simplest example follows: var Start, Stop, ElapsedMilliseconds: cardinal; begin Start := GetTickCount; // do something that requires measurement Stop := GetTickCount; ...

Appearance : Happens when your script tries to send a HTTP header to the client but there already was output before, which resulted in headers to be already sent to the client. Possible Causes : Print, echo: Output from print and echo statements will terminate the opportunity to send HTTP hea...

The below code example will give you an adjusted version of that color where a higher percentage will be brighter and a lower percentage will be darker. Objective-C + (UIColor *)adjustedColorForColor:(UIColor *)c : (double)percent { if (percent < 0) percent = 0; CGFloat r, g, b...

We will parse the highlighted tag data through NSXMLParser We have declared few properties as follows @property(nonatomic, strong)NSMutableArray *results; @property(nonatomic, strong)NSMutableString *parsedString; @property(nonatomic, strong)NSXMLParser *xmlParser; //Fetch xml data NSURLSe...

Pan gesture recognizers detect dragging gestures. The following example adds an image to a view controller and lets the user drag it around on screen. Objective-C - (void)viewDidLoad { [super viewDidLoad]; UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNa...

Premise The most confusing thing surrounding pointer syntax in C and C++ is that there are actually two different meanings that apply when the pointer symbol, the asterisk (*), is used with a variable. Example Firstly, you use * to declare a pointer variable. int i = 5; /* 'p' is a pointer to a...

When performing tasks asynchronously there typically becomes a need to ensure a piece of code is run on the main thread. For example you may want to hit a REST API asynchronously, but put the result in a UILabel on the screen. Before updating the UILabel you must ensure that your code is run on th...

Move every outlet to an NSObject. Then drag an Object from the library to the controller scene of the storyboard and hook the elements there. class ContactFormStyle: NSObject { @IBOutlet private weak var message: UILabel! { didSet { message.font = UIFont.systemFontOfSize(12) ...

Strings can be assigned directly to byte arrays and visa-versa. Remember that Strings are stored in a Multi-Byte Character Set (see Remarks below) so only every other index of the resulting array will be the portion of the character that falls within the ASCII range. Dim bytes() As Byte Dim exampl...

Add a key named Required background modes in property list (.plist) file .. as following picture.. And add following code in AppDelegate.h #import <AVFoundation/AVFoundation.h> #import <AudioToolbox/AudioToolbox.h> AppDelegate.m in application didFinishLaunchingWithOptions [[...

let view = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100)) view.backgroundColor = UIColor.orange self.view.addSubview(view) UIView.animate(withDuration: 0.75, delay: 0.5, options: .curveEaseIn, animations: { //This will cause view to go from (0,0) to // (self.view.frame.origi...

Suppose you have two lists: A and B, and you need to find the elements that exist in both lists. You can do it by just invoking the method List.retainAll(). Example: public static void main(String[] args) { List<Integer> numbersA = new ArrayList<>(); List<Integer> numb...

The following is a simple example of using the strategy pattern without a context class. There are two implementation strategies which implement the interface and solve the same problem in different ways. Users of the EnglishTranslation class can call the translate method and choose which strategy t...

Intent: Define an interface for creating an object, but let sub classes decide which class to instantiate. Factory Method lets a class defer instantiation to sub classes. UML diagram: Product: It defines an interface of the objects the Factory method creates. ConcreteProduct: Implements Produc...