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yii migrate/history # showing the last 10 applied migrations yii migrate/history 5 # showing the last 5 applied migrations yii migrate/history all # showing all applied migrations yii migrate/new # showing the first 10 new migrations yii migrate/new 5 # showing the first 5 ...

yii migrate/mark 150101_185401 # using timestamp to specify the migration yii migrate/mark "2015-01-01 18:54:01" # using a string that can be parsed by strtotime() yii migrate/mark m150101_185401_create_news_table # using full name yii migrate/mark 13...

yii migrate This command will list all migrations that have not been applied so far. If you confirm that you want to apply these migrations, it will run the up() or safeUp() method in every new migration class, one after another, in the order of their timestamp values. If any of the migrations fa...

An abstract class is a class that cannot be instantiated. Abstract classes can define abstract methods, which are methods without any body, only a definition: abstract class MyAbstractClass { abstract public function doSomething($a, $b); } Abstract classes should be extended by a child cla...

AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder( MainActivity.this); alertDialogBuilder.setTitle("Title Dialog"); alertDialogBuilder .setMessage("Message Dialog") .setCancelable(true) ...

SELECT * FROM table1, table2 SELECT table1.column1, table1.column2, table2.column1 FROM table1, table2 This is called cross product in SQL it is same as cross product in sets These statements return the selected columns from multiple tables in one query....

Set memory limit and disable swap limit docker run -it -m 300M --memory-swap -1 ubuntu:14.04 /bin/bash Set both memory and swap limit. In this case, container can use 300M memory and 700M swap. docker run -it -m 300M --memory-swap 1G ubuntu:14.04 /bin/bash

WCF tracing is built on top of System.Diagnostics. To use tracing, you should define trace sources in the configuration file or in code. Tracing is not enabled by default. To activate tracing, you must create a trace listener and set a trace level other than "Off" for the selected trace s...

We can use Predefined Constants for Date format in date() instead of the conventional date format strings since PHP 5.1.0. Predefined Date Format Constants Available DATE_ATOM - Atom (2016-07-22T14:50:01+00:00) DATE_COOKIE - HTTP Cookies (Friday, 22-Jul-16 14:50:01 UTC) DATE_RSS - RSS (Fri, 22...

Installation Requirements The minimum requirement by this project template is that your Web server supports PHP 5.4.0. Yii2-advanced-app can be installed in two ways. They are Installing via Composer Installing from an Archive File 1) Installing via Composer If you do not already have Comp...

First, download the compiler and components. Next, add Swift to your path. On macOS, the default location for the downloadable toolchain is /Library/Developer/Toolchains. Run the following command in Terminal: export PATH=/Library/Developer/Toolchains/swift-latest.xctoolchain/usr/bin:"${PATH}...

Technically, autoloading works by executing a callback when a PHP class is required but not found. Such callbacks usually attempt to load these classes. Generally, autoloading can be understood as the attempt to load PHP files (especially PHP class files, where a PHP source file is dedicated for a ...

An anonymous function is just a function that doesn't have a name. // Anonymous function function() { return "Hello World!"; }; In PHP, an anonymous function is treated like an expression and for this reason, it should be ended with a semicolon ;. An anonymous function should b...

Program units often make use of literal constants. These cover the obvious cases like print *, "Hello", 1, 1.0 Except in one case, each literal constant is a scalar which has type, type parameters and value given by the syntax. Integer literal constants are of the form 1 -1 -1_1 ...

You can call a function in Racket by wrapping it in parentheses with the arguments after it. This looks like (function argument ...). > (define (f x) x) > (f 1) 1 > (f "salmon") "salmon" > (define (g x y) (string-append x y)) > (g "large" "sal...

A common pattern in C# is using bool TryParse(object input, out object value) to safely parse objects. The out var declaration is a simple feature to improve readability. It allows a variable to be declared at the same time that is it passed as an out parameter. A variable declared this way is sco...

The 0b prefix can be used to represent Binary literals. Binary literals allow constructing numbers from zeroes and ones, which makes seeing which bits are set in the binary representation of a number much easier. This can be useful for working with binary flags. The following are equivalent ways o...

The underscore _ may be used as a digit separator. Being able to group digits in large numeric literals has a significant impact on readability. The underscore may occur anywhere in a numeric literal except as noted below. Different groupings may make sense in different scenarios or with different ...

Basics A tuple is an ordered, finite list of elements. Tuples are commonly used in programming as a means to work with one single entity collectively instead of individually working with each of the tuple's elements, and to represent individual rows (ie. "records") in a relational databa...

Local functions are defined within a method and aren't available outside of it. They have access to all local variables and support iterators, async/await and lambda syntax. This way, repetitions specific to a function can be functionalized without crowding the class. As a side effect, this improves...