Tutorial by Examples: lit

This solution uses the ora:tokenize XQuery function that is available from Oracle 11. Sample Data: CREATE TABLE table_name ( id, list ) AS SELECT 1, 'a,b,c,d' FROM DUAL UNION ALL -- Multiple items in the list SELECT 2, 'e' FROM DUAL UNION ALL -- Single item in the list SELECT 3, NULL ...

In the Project.pro file we add : CONFIG += sql in MainWindow.h we write : #include <QMainWindow> #include <QSql> #include <QDebug> namespace Ui { class MainWindow; } class MainWindow : public QMainWindow { Q_OBJECT public: explicit MainWindow(QWidget...

Converter between boolean and visibility. Get bool value on input and returns Visibility value. NOTE: This converter have already exists in System.Windows.Controls namespace. public sealed class BooleanToVisibilityConverter : IValueConverter { /// <summary> /// Convert bool or Nu...

Customizing the Shell prompt Default command prompt can be changed to look different and short. In case the current directory is long default command prompt becomes too large. Using PS1 becomes useful in these cases. A short and customized command pretty and elegant. In the table below PS1 has be...

Angular js directives can be nested or be made interoperable. In this example, directive Adir exposes to directive Bdir it's controller $scope, since Bdir requires Adir. angular.module('myApp',[]).directive('Adir', function () { return { restrict: 'AE', controlle...

When to use abstract classes: To implement the same or different behaviour among multiple related objects When to use interfaces: to implement a contract by multiple unrelated objects Abstract classes create "is a" relations while interfaces provide "has a" capability. This c...

When expecting someone to reproduce an R code that has random elements in it, the set.seed() function becomes very handy. For example, these two lines will always produce different output (because that is the whole point of random number generators): > sample(1:10,5) [1] 6 9 2 7 10 >...

Also known as triple equals. This operator does not test equality, but rather tests if the right operand has an IS A relationship with the left operand. As such, the popular name case equality operator is misleading. This SO answer describes it thus: the best way to describe a === b is "if I ...

dput() and dget() The easiest way to share a (preferable small) data frame is to use a basic function dput(). It will export an R object in a plain text form. Note: Before making the example data below, make sure you're in an empty folder you can write to. Run getwd() and read ?setwd if you need t...

Package reproducibility is a very common issue in reproducing some R code. When various packages get updated, some interconnections between them may break. The ideal solution for the problem is to reproduce the image of the R code writer's machine on your computer at the date when the code was writt...

You may sometimes want to change the size of a split or vsplit. To change the size of the currently active split, use :resize <new size>. :resize 30 for example would make the split 30 lines tall. To change the size of the currently active vsplit, use :vertical resize <new size>. :vert...

A compound literal is an unnamed object which is created in the scope where is defined. The concept was first introduced in C99 standard. An example for compound literal is Examples from C standard, C11-§6.5.2.5/9: int *p = (int [2]){ 2, 4 }; p is initialized to the address of the first ele...

Stateful iterators carry some additional information about the current state of the iterator. Using Tables The addition state can be packed into the generic for loop's invariant state. local function chars_iter(t, i) local i = i + 1 if i <= t.len then return i, t.s:sub(i, i)...

Developing Meteor apps usually means developing multi-client reactivity, which requires collaboration tools. The following tools have proven to be popular within the Meteor community. Google Hangouts - Video conferencing and chat. Zenhub.io - Kanban boards for GitHub. InVision - Collaborative ...

In C, character constants and string literals are different things. A character surrounded by single quotes like 'a' is a character constant. A character constant is an integer whose value is the character code that stands for the character. How to interpret character constants with multiple charac...

SQLite is a lightweight, disk-based database. Since it does not require a separate database server, it is often used for prototyping or for small applications that are often used by a single user or by one user at a given time. import sqlite3 conn = sqlite3.connect("users.db") c = con...

In Swift you can easily separate a String into an array by slicing it at a certain character: 3.0 let startDate = "23:51" let startDateAsArray = startDate.components(separatedBy: ":") // ["23", "51"]` 2.2 let startDate = "23:51" let sta...

In Julia, a for loop can contain a comma (,) to specify iterating over multiple dimensions. This acts similarly to nesting a loop within another, but can be more compact. For instance, the below function generates elements of the Cartesian product of two iterables: function cartesian(xs, ys) f...

Splits some partition into two partitions with another high bound. ALTER TABLE table_name SPLIT PARTITION old_partition AT (new_high_bound) INTO (PARTITION new_partition TABLESPACE new_tablespace, PARTITION old_partition)

Even experienced Java developers tend to think that Java has only three protection modifiers. The language actually has four! The package private (a.k.a. default) level of visibility is often forgotten. You should pay attention to what methods you make public. The public methods in an application a...