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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;

The difference in months between two dates can be found using the MONTHS_BETWEEN( date1, date2 ): SELECT MONTHS_BETWEEN( DATE '2016-03-10', DATE '2015-03-10' ) AS difference FROM DUAL; Outputs: DIFFERENCE ---------- 12 If the difference includes part months then it will return the ...

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

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...

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...

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...

This is similar in syntax to the example that initializes using positional constants, but requires the Then extension from https://github.com/devxoul/Then (attached below). let label = UILabel().then { $0.textAlignment = .Center $0.textColor = UIColor.blackColor( $0.text = "Hell...

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...

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...

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...

The Builder pattern allows you to create an instance of a class with many optional variables in an easy to read way. Consider the following code: public class Computer { public GraphicsCard graphicsCard; public Monitor[] monitors; public Processor processor; public Memory[] r...

Input.acceleration is used to read the accelerometer sensor. It returns Vector3 as a result which contains x,y and z axis values in 3D space. void Update() { Vector3 acclerometerValue = rawAccelValue(); Debug.Log("X: " + acclerometerValue.x + " Y: " + acclerometerV...

'use strict'; const co = require('co'); module.exports = { // This is the index action and the route is mapped via /config/routes.js index(req, res) { co(function* index() { // Return a view without view model data // This typically will return the view defined at /vie...

Converting between encodings is easy with C++11 and most compilers are able to deal with it in a cross-platform manner through <codecvt> and <locale> headers. #include <iostream> #include <codecvt> #include <locale> #include <string> using namespace std; i...

When a user press F1 on a control or click on Help button of form (?) and then clicks on a control the HelpRequested event will be raised. You can handle this event to provide custom action when user requests help for controls or form. The HelpRequested supports bubble up mechanism. It fires for y...

You can detect when a user Clicked on a HelpButton on title-bar of form by handling HelpButtonClicked. You can let the event continue or cancel it by setting Cancel property of its event args to true. private void Form1_HelpButtonClicked(object sender, CancelEventArgs e) { e.Cancel = true; ...

Using raw values directly from the accelerometer sensor to move or rotate a GameObject can cause problems such as jerky movements or vibrations. It is recommended to smooth out the values before using them. In fact, values from the accelerometer sensor should always be smoothed out before use. This ...

The contents of files and network messages may represent encoded characters. They often need to be converted to unicode for proper display. In Python 2, you may need to convert str data to Unicode characters. The default ('', "", etc.) is an ASCII string, with any values outside of ASCII ...

Assignment arguments appear at the end of an awk invocation, in the same area as file variables, both -v assignments and argument assignments must match the following regular expression. (assuming a POSIX locale) ^[[:alpha:]_][[:alnum:]_]*= The following example assumes a file file containing th...

This will trigger the native email client for sharing text. Parameters : Email To address, Subject, Body. Code Sample : you can call the function wherever you need, (mostly inside click listeners) like below Calling function shareEmail("[email protected]", "Email sharing example&q...