Tutorial by Examples: nd

Compound assignment operators

SQL Server 2008 R2 Supported compound operators: += Add and assign -= Subtract and assign *= Multiply and assign /= Divide and assign %= Modulo and assign &= Bitwise AND and assign ^= Bitwise XOR and assign |= Bitwise OR and assign Example usage: DECLARE @test INT = 42; SET @test...

Microsoft SQL Server • Variables

Join parent and child JSON entities using CROSS APPLY OPENJSON

Join parent objects with their child entities, for example we want a relational table of each person and their hobbies DECLARE @json nvarchar(1000) = N'[ { "id":1, "user":{"name":"John"}, "hobbies":[ {...

Microsoft SQL Server • JSON in Sql Server

Programmatically adding a metadata endpoint to a service

When you also want to expose metadata without a config file you can build on the example programmatically creating a ServiceHost: public ConsoleHost() { mHost = new ServiceHost(typeof(Example), new Uri("http://localhost:8000/Example"), new Uri("net.tcp://9000/Example")); ...

wcf • Your first service

Place allocation and cleanup code next to each other

Scope guards allow executing statements at certain conditions if the current block is left. import core.stdc.stdlib; void main() { int* p = cast(int*)malloc(int.sizeof); scope(exit) free(p); }

D Language • Scope guards

Unit Testing Promises with Mocha, Sinon, Chai and Proxyquire

Here we have a simple class to be tested that returns a Promise based on the results of an external ResponseProcessor that takes time to execute. For simplicty we'll assume that the processResponse method won't ever fail. import {processResponse} from '../utils/response_processor'; const ping =...

JavaScript • Unit Testing Javascript

Renamed and selective imports

Selective imports may also be renamed. void main() { import std.stdio : fooln = writeln; fooln("Hello world"); }

D Language • Imports and modules

Find all matches

Using using System.Text.RegularExpressions; Code static void Main(string[] args) { string input = "Carrot Banana Apple Cherry Clementine Grape"; // Find words that start with uppercase 'C' string pattern = @"\bC\w*\b"; MatchCollection matches = Regex.M...

.NET Framework • Regular Expressions (System.Text.RegularExpressions)

Grant and Revoke Privileges.

Suppose, that we have three users : The Administrator of the database > admin The application with a full access for her data > read_write The read only access > read_only --ACCESS DB REVOKE CONNECT ON DATABASE nova FROM PUBLIC; GRANT CONNECT ON DATABASE nova TO user; With th...

postgresql • Role Management

Terminology and Structure

Media queries allow one to apply CSS rules based on the type of device / media (e.g. screen, print or handheld) called media type, additional aspects of the device are described with media features such as the availability of color or viewport dimensions. General Structure of a Media Query @media ...

CSS • Media Queries

Indent code properly

Proper indentation gives not only the aesthetic look but also increases the readability of the code. For example, consider the following code: %no need to understand the code, just give it a look n = 2; bf = false; while n>1 for ii = 1:n for jj = 1:n if ii+jj>30 bf = true; break end...

MATLAB Language • MATLAB Best Practices

Testing using setUp and tearDown function

You can set a setUp and tearDown function. A setUp function prepares your environment to tests. A tearDown function does a rollback. This is a good option when you can't modify your database and you need to create an object that simulate an object brought of database or need to init a configu...

Go • Testing

stroke (a path command)

context.stroke() Causes the perimeter of the Path to be stroked according to the current context.strokeStyle and the stroked Path is visually drawn onto the canvas. Prior to executing context.stroke (or context.fill) the Path exists in memory and is not yet visually drawn on the canvas. The unu...

html5-canvas • Path (Syntax only)

fill (a path command)

context.fill() Causes the inside of the Path to be filled according to the current context.fillStyle and the filled Path is visually drawn onto the canvas. Prior to executing context.fill (or context.stroke) the Path exists in memory and is not yet visually drawn on the canvas. Example code usi...

html5-canvas • Path (Syntax only)

clip (a path command)

context.clip Limits any future drawings to display only inside the current Path. Example: Clip this image into a triangular Path <!doctype html> <html> <head> <style> body{ background-color:white; } #canvas{border:1px solid red; } </style> <sc...

html5-canvas • Path (Syntax only)

NLTK installation with Conda.

To install NLTK with Continuum's anaconda / conda. If you are using Anaconda, most probably nltk would be already downloaded in the root (though you may still need to download various packages manually). Using conda: conda install nltk To upgrade nltk using conda: conda update nltk With a...

nltk • Getting started with nltk

Find smallest prime factor

In some situations, one might want to return from a function before finishing an entire loop. The return statement can be used for this. function primefactor(n) for i in 2:n if n % i == 0 return i end end @assert false # unreachable end Usage: jul...

Julia Language • for Loops

Reduction and parallel loops

Julia provides macros to simplify distributing computation across multiple machines or workers. For instance, the following computes the sum of some number of squares, possibly in parallel. function sumofsquares(A) @parallel (+) for i in A i ^ 2 end end Usage: julia> sumo...

Julia Language • for Loops

Ternary conditional operator

pushunique!(A, x) = x in A ? A : push!(A, x) The ternary conditional operator is a less wordy if...else expression. The syntax specifically is: [condition] ? [execute if true] : [execute if false] In this example, we add x to the collection A only if x is not already in A. Otherwise, we jus...

Julia Language • Conditionals

Short-circuit operators: && and ||

For branching The short-circuiting conditional operators && and || can be used as lightweight replacements for the following constructs: x && y is equivalent to x ? y : x x || y is equivalent to x ? x : y One use for short-circuit operators is as a more concise way to test a ...

Julia Language • Conditionals

Oozie Application Deployment

A simplest Oozie application is consists of a workflow logic file (workflow.xml), workflow properties file (job.properties/job.xml) and required JAR files, scripts and configuration files. Except the workflow properties file, all the other files should to be stored in a HDFS location. The workflow p...

oozie • Oozie 101