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A database snapshot is a read-only, static view of a SQL Server database (the source database). It is similar to backup, but it is available as any other database so client can query snapshot database. CREATE DATABASE MyDatabase_morning -- name of the snapshot ON ( NAME=MyDatabase_data, -- l...

If data in a source database becomes damaged or some wrong data is written into database, in some cases, reverting the database to a database snapshot that predates the damage might be an appropriate alternative to restoring the database from a backup. RESTORE DATABASE MYDATABASE FROM DATABASE_SNAP...

Here's the 'bare minimum' Arduino sketch. This can be loaded into the Arduino IDE by choosing File > Examples > 01. Basics > Bare Minimum. void setup() { // put your setup code here, to run once } void loop() { // put your main code here, to run repeatedly } Code in the setup...

docker run hello-world This will fetch the latest hello-world image from the Docker Hub (if you don't already have it), create a new container, and run it. You should see a message stating that your installation appears to be working correctly.

docker run docker/whalesay cowsay 'Hello, StackExchange!' This command tells Docker to create a container from the docker/whalesay image and run the command cowsay 'Hello, StackExchange!' in it. It should print a picture of a whale saying Hello, StackExchange! to your terminal. If the entrypoin...

Normally, a Docker container persists after it has exited. This allows you to run the container again, inspect its filesystem, and so on. However, sometimes you want to run a container and delete it immediately after it exits. For example to execute a command or show a file from the filesystem. Dock...

In this example we will write a basic program that checks the number of inputs and outputs passed to a MEX-function. As a starting point, we need to create a C++ file implementing the "MEX gateway". This is the function executed when the file is called from MATLAB. testinputs.cpp // Mat...

git add -i (or --interactive) will give you an interactive interface where you can edit the index, to prepare what you want to have in the next commit. You can add and remove changes to whole files, add untracked files and remove files from being tracked, but also select subsection of changes to put...

SELECT * FROM Employees WHERE ManagerId IS NULL This statement will return all Employee records where the value of the ManagerId column is NULL. The result will be: Id FName LName PhoneNumber ManagerId DepartmentId 1 James Smith 1234567890 NULL 1 SEL...

Alt-text is used by screen readers for visually impaired users and by search engines. It's therefore important to write good alt-text for your images. The text should look correct even if you replace the image with its alt attribute. For example: <!-- Incorrect --> <img src="anonymo...

An std::map takes (key, value) pairs as input. Consider the following example of std::map initialization: std::map < std::string, int > ranking { std::make_pair("stackoverflow", 2), std::make_pair("docs-beta", 1) }; In an std::...

std::map and std::multimap both can be initialized by providing key-value pairs separated by comma. Key-value pairs could be provided by either {key, value} or can be explicitly created by std::make_pair(key, value). As std::map does not allow duplicate keys and comma operator performs right to left...

std::map or std::multimap could be traversed by the following ways: std::multimap< int , int > mmp{ {1, 2}, {3, 4}, {6, 5}, {8, 9}, {3, 4}, {6, 7} }; //Range based loop - since C++11 for(const auto &x: mmp) std::cout<< x.first <<":...

There are several ways to search a key in std::map or in std::multimap. To get the iterator of the first occurrence of a key, the find() function can be used. It returns end() if the key does not exist. std::multimap< int , int > mmp{ {1, 2}, {3, 4}, {6, 5}, {8, 9}, {3, 4}, {6, 7} }; ...

INSERT INTO Customers (FName, LName, PhoneNumber) SELECT FName, LName, PhoneNumber FROM Employees This example will insert all Employees into the Customers table. Since the two tables have different fields and you don't want to move all the fields over, you need to set which fields to insert int...

The "default" for constructors is that they do not have any arguments. In case you do not specify any constructor, the compiler will generate a default constructor for you. This means the following two snippets are semantically equivalent: public class TestClass { private String tes...

Constructors can be created with any kinds of arguments. public class TestClass { private String testData; public TestClass(String testData) { this.testData = testData; } } Called like this: TestClass testClass = new TestClass("Test Data"); A class can ...

Each individual CSS Selector has its own specificity value. Every selector in a sequence increases the sequence's overall specificity. Selectors fall into one of three different specificity groups: A, B and c. When multiple selector sequences select a given element, the browser uses the styles appli...

Node.js package configurations are contained in a file called package.json that you can find at the root of each project. You can setup a brand new configuration file by calling: npm init That will try to read the current working directory for Git repository information (if it exists) and enviro...

The Lua standard library provides a pairs function which iterates over the keys and values of a table. When iterating with pairs there is no specified order for traversal, even if the keys of the table are numeric. for key, value in pairs(input_table) do print(key, " -- ", value) en...