Tutorial by Examples: d

Omitting a WHERE clause will delete all rows from a table. DELETE FROM Employees See TRUNCATE documentation for details on how TRUNCATE performance can be better because it ignores triggers and indexes and logs to just delete the data.

When pattern matching an object whose type is a sealed trait, Scala will check at compile-time that all cases are 'exhaustively matched': sealed trait Shape case class Square(height: Int, width: Int) extends Shape case class Circle(radius: Int) extends Shape case object Point extends Shape ...

A popular form of data analysis is split-apply-combine, in which you split your data into groups, apply some sort of processing on each group, and then combine the results. Let's consider a data analysis where we want to obtain the two cars with the best miles per gallon (mpg) for each cylinder cou...

Slices have both length and capacity. The length of a slice is the number of elements currently in the slice, while the capacity is the number of elements the slice can hold before needing to be reallocated. When creating a slice using the built-in make() function, you can specify its length, and ...

The latest SDK can be downloaded here The latest SDK libraries are also available on NuGet under Microsoft's official crmsdk account

Display all data files for all databases with size and growth info SELECT d.name AS 'Database', d.database_id, SF.fileid, SF.name AS 'LogicalFileName', CASE SF.status & 0x100000 WHEN 1048576 THEN 'Percentage' WHEN 0 THEN 'MB...

It's a bad idea to hard code paths in your application. One should always use relative urls so that your code can work seamlessly across different machines. The best way to set this up is to define a variable like this import os BASE_DIR = os.path.dirname(os.path.dirname(__file__)) Then use th...

public enum DayOfWeek { Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } // Enum to string string thursday = DayOfWeek.Thursday.ToString(); // "Thursday" string seventhDay = Enum.GetName(typeof(DayOfWeek), 6); // "Satur...

Joins can also be used in an UPDATE statement: CREATE TABLE Users ( UserId int NOT NULL, AccountId int NOT NULL, RealName nvarchar(200) NOT NULL ) CREATE TABLE Preferences ( UserId int NOT NULL, SomeSetting bit NOT NULL ) Update the SomeSetting column of the Prefere...

connection.Execute(@"some Query with @a,@b,@c", new {a=somevalueOfa,b=somevalueOfb,c=somevalueOfc});

Media Queries in Bootstrap allow you to move, show and hide content based on the viewport size. The following media queries are used in LESS files to create the key breakpoints in the Bootstrap grid system: /* Small devices (tablets, 768px and up) */ @media (min-width: @screen-sm-min) { ... } /...

You can create a new hash with the keys or values modified, indeed you can also add or delete keys, using inject (AKA, reduce). For example to produce a hash with stringified keys and upper case values: fruit = { name: 'apple', color: 'green', shape: 'round' } # => {:name=>"apple",...

The background property can be used to set one or more background related properties: ValueDescriptionCSS Ver.background-imageBackground image to use1+background-colorBackground color to apply1+background-positionBackground image's position1+background-sizeBackground image's size3+background-repeat...

You may add your new Seeder to the DatabaseSeeder class. /** * Run the database seeds. * * @return void */ public function run() { $this->call(UserTableSeeder::class); } To run a database seeder, use the Artisan command php artisan db:seed ...

Database seeds are stored in the /database/seeds directory. You can create a seed using an Artisan command. php artisan make:seed UserTableSeeder Alternatively you can create a new class which extends Illuminate\Database\Seeder. The class must a public function named run().

You can reference models in a seeder. use DB; use App\Models\User; class UserTableSeeder extends Illuminate\Database\Seeder{ public function run(){ # Remove all existing entrie DB::table('users')->delete() ; User::create([ 'name' => 'Admin', ...

There are two things you will need to know when writing a "hello world" application in Erlang: The source code is written in the erlang programming language using the text editor of your choice The application is then executed in the erlang virtual machine. In this example we will inte...

Structure data types are useful way to package related data and have them behave like a single variable. Declaring a simple struct that holds two int members: struct point { int x; int y; }; x and y are called the members (or fields) of point struct. Defining and using structs: ...

Nginx is a Web server used to serve HTTP requests over the Internet. Nginx is available on Linux, Windows and other OSes as direct download, and can also be built from source. For detailed instructions see Nginx official reference. ubuntu/debian nginx stable version is available in official repo,...

While the Java Date class has several constructors, you'll notice that most are deprecated. The only acceptable way of creating a Date instance directly is either by using the empty constructor or passing in a long (number of milliseconds since standard base time). Neither are handy unless you're lo...