Tutorial by Examples: u

Often when writing a specialized class, you'll want it to raise its own specific errors, and you'll want a clean way for user/calling code to handle these custom errors. A neat way to achieve this is by defining a dedicated Enum type: Option Explicit Public Enum FoobarError Err_FooWasNotBarre...

This script, from here and here, will return all Tables and Columns where a specified value exists. This is powerful in finding out where a certain value is in a database. It can be taxing, so it is suggested that it be executed in a backup / test enviroment first. DECLARE @SearchStr nvarchar(100) ...

SELECT ps.name AS PartitionScheme , fg.name AS [FileGroup] , prv.* , LAG(prv.Value) OVER (PARTITION BY ps.name ORDER BY ps.name, boundary_id) AS PreviousBoundaryValue FROM sys.partition_schemes ps INNER JOIN sys.destination_data...

Using the Authors table in the Library Database CREATE PROCEDURE GetName ( @input_id INT = NULL, --Input parameter, id of the person, NULL default @name VARCHAR(128) = NULL --Input parameter, name of the person, NULL default ) AS BEGIN SELECT Name + ' is from ' + Country...

Directives can be used to build reusable components. Here is an example of a "user box" component: userBox.js angular.module('simpleDirective', []).directive('userBox', function() { return { scope: { username: '=username', reputation: '=reputation' }, ...

Once Powershell remoting is enabled (Enable-PSRemoting) You can run commands on the remote computer like this: Invoke-Command -ComputerName "RemoteComputerName" -ScriptBlock { Write host "Remote Computer Name: $ENV:ComputerName" } The above method creates a temporary se...

UPDATE HelloWorlds SET HelloWorld = 'HELLO WORLD!!!' WHERE Id = 5 The above code updates the value of the field "HelloWorld" with "HELLO WORLD!!!" for the record where "Id = 5" in HelloWorlds table. Note: In an update statement, It is advised to use a "where&...

A simple form of updating is incrementing all the values in a given field of the table. In order to do so, we need to define the field and the increment value The following is an example that increments the Score field by 1 (in all rows): UPDATE Scores SET score = score + 1 This can be dang...

We will use the built in tooth growth dataset. We are interested in whether there is a statistically significant difference in tooth growth when the guinea pigs are given vitamin C vs orange juice. Here's the full example: teethVC = ToothGrowth[ToothGrowth$supp == 'VC',] teethOJ = ToothGrowth[To...

The rep function can be used to repeat a vector in a fairly flexible manner. # repeat counting numbers, 1 through 5 twice rep(1:5, 2) [1] 1 2 3 4 5 1 2 3 4 5 # repeat vector with incomplete recycling rep(1:5, 2, length.out=7) [1] 1 2 3 4 5 1 2 The each argument is especially useful for ex...

var multiplexer = ConnectionMultiplexer.Connect("localhost"); IDatabase db = multiplexer.GetDatabase(); // intialize key with empty string await db.StringSetAsync("key", ""); // create transaction that utilize multiplexing and pipelining ITransaction transacton...

History The first computers Early computers had a block of memory that the programmer put code and data into, and the CPU executed within this environment. Given that the computers then were very expensive, it was unfortunate that it would do one job, stop and wait for the next job to be loaded in...

When the Pentium was being developed, memory sizes, and the programs that ran in them, were getting larger. The OS had to do more and more work to maintain the Paging Subsystem just in the sheer number of Page Indexes that needed to be updated when large programs or data sets were being used. So th...

class Program { private static Lazy<ConnectionMultiplexer> _multiplexer = new Lazy<ConnectionMultiplexer>( () => ConnectionMultiplexer.Connect("localhost"), LazyThreadSafetyMode.ExecutionAndPublication); static void Main(string[] args...

Connect to Redis server and allow admin (risky) commands ConfigurationOptions options = new ConfigurationOptions() { EndPoints = { { "localhost", 6379}}, AllowAdmin = true, ConnectTimeout = 60*1000, }; Connectio...

This example will show you how to create a Windows Forms Application project in Visual Studio. Create Windows Forms Project Start Visual Studio. On the File menu, point to New, and then select Project. The New Project dialog box appears. In the Installed Templates pane, select "...

Open a text editor (like Notepad), and type the code below: using System; using System.ComponentModel; using System.Drawing; using System.Windows.Forms; namespace SampleApp { public class MainForm : Form { private Button btnHello; // The form's con...

6 ES6: myFunction.name Explanation on MDN. As of 2015 works in nodejs and all major browsers except IE. 5 ES5: If you have a reference to the function, you can do: function functionName( func ) { // Match: // - ^ the beginning of the string // - function the w...

docker run -d --name "mysql-1" -v "/var/lib/mysql" mysql This command creates a new container from the mysql image. It also creates a new data volume, which it then mounts in the container at /var/lib/mysql. This volume helps any data inside of it persist beyond the lifetime o...

Many interesting operations in common JavaScript programming environments are asynchronous. For example, in the browser we see things like window.setTimeout(() => { console.log("this happens later"); }, 100); and in Node.js we see things like fs.readFile("file.txt", (...