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In C, a string is a sequence of characters that is terminated by a null character ('\0'). We can create strings using string literals, which are sequences of characters surrounded by double quotation marks; for example, take the string literal "hello world". String literals are automatica...

An array of strings can mean a couple of things: An array whose elements are char *s An array whose elements are arrays of chars We can create an array of character pointers like so: char * string_array[] = { "foo", "bar", "baz" }; Remember: w...

A minimal CMake project file that uses Qt5 can be: cmake_minimum_required(VERSION 2.8.11) project(myproject) find_package(Qt5 5.7.0 REQUIRED COMPONENTS Core ) set(CMAKE_AUTOMOC ON) add_executable(${PROJECT_NAME} main.cpp ) target_link_libraries(${PROJECT_NAME} Qt5::C...

If you use an index that is sorted the way you would retrieve it, the SELECT statement would not do additional sorting when in retrieval. CREATE INDEX ix_scoreboard_score ON scoreboard (score DESC); When you execute the query SELECT * FROM scoreboard ORDER BY score DESC; The database system ...

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(QWid...

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...

Layout Unity basic editor will look like below. Basic functionalities of some default windows/tabs are described in the image. Linux Layout There is a little difference in menu layout of linux version, like the screenshot below, Basic Usage Create an empty GameObject by right clicking in th...

Using the default constructor T variable = Activator.CreateInstance(typeof(T)); Using parameterized constructor T variable = Activator.CreateInstance(typeof(T), arg1, arg2);

Occasionally you'd want to catch an exception and throw it from a different thread or method while preserving the original exception stack. This can be done with ExceptionDispatchInfo: using System.Runtime.ExceptionServices; void Main() { ExceptionDispatchInfo capturedException = null; ...

Due to logical query processing order, alias can be used in order by. SELECT DisplayName, JoinDate as jd, Reputation as rep FROM Users ORDER BY jd, rep And can use relative order of the columns in the select statement .Consider the same example as above and instead of using alias use the relat...

Whenever a Python script is invoked from the command line, the user may supply additional command line arguments which will be passed on to the script. These arguments will be available to the programmer from the system variable sys.argv ("argv" is a traditional name used in most programmi...

You can count the number of rows: SELECT count(*) TotalRows FROM employees; TotalRows4 Or count the employees per department: SELECT DepartmentId, count(*) NumEmployees FROM employees GROUP BY DepartmentId; DepartmentIdNumEmployees1321 You can count over a column/expression with the eff...

REST stands for REpresentational State Transfer and was coined by Roy Fielding in his doctoral thesis Architectural Styles and the Design of Network-based Software Architectures. In it he identifies specific architectural principles like: Addressable Resources: the key abstraction of informatio...

To install Eclipse RCP follow the steps : Download Eclipse RCP/RAP version from Eclipse.org Eclipse RCP/RAP project downloading URL

If you are able to download an update of Android Studio, but after it restarts nothing happens, check out the following example: After the patch was downloaded and Android Studio closed, open the terminal Go to your android studio folder, e.g. cd ~/android-studio Go to bin subfolder: cd bin ...

.NET Framework defines a interface for types requiring a tear-down method: public interface IDisposable { void Dispose(); } Dispose() is primarily used for cleaning up resources, like unmanaged references. However, it can also be useful to force the disposing of other resources even though ...

Messages printed from NSLog are displayed on Console.app even in the release build of your app, which doesn't make sense for printouts that are only useful for debugging. To fix this, you can use this macro for debug logging instead of NSLog. #ifdef DEBUG #define DLog(...) NSLog(__VA_ARGS__) #els...

First, import the libraries that work with files: from os import listdir from os.path import isfile, join, exists A helper function to read only files from a directory: def get_files(path): for file in listdir(path): full_path = join(path, file) if isfile(full_path): ...

Syntax: add_months(p_date, integer) return date; Add_months function adds amt months to p_date date. SELECT add_months(date'2015-01-12', 2) m FROM dual; M2015-03-12 You can also substract months using a negative amt SELECT add_months(date'2015-01-12', -2) m FROM dual; M2014-11-12 When the...

public static class ThreadLocalExample { private static final ThreadLocal<SimpleDateFormat> format = ThreadLocal.withInitial(() -> new SimpleDateFormat("yyyyMMdd_HHmm")); public String formatDate(Date date) { return format.get().format(date); ...