Tutorial by Examples: ble

This query will return all COLUMNS and their associated TABLES for a given column name. It is designed to show you what tables (unknown) contain a specified column (known) SELECT c.name AS ColName, t.name AS TableName FROM sys.columns c JOIN sys.tables t ON c.object_id = t.o...

Comparable types are primitive types that can be compared using comparison operators from Basics module, like: (<), (>), (<=), (>=), max, min, compare Comparable types in Elm are Int, Float, Time, Char, String, and tuples or lists of comparable types. In documentation or type definitio...

If you have a value that you use often, you can store it in a variable. You could use this to define color schemes, for example. You would only have to define your scheme once and then you could use it throughout your stylesheets. To define a variable, you must prefix its name with the $ symbol. (L...

Implementing the IEnumerable interface allows classes to be enumerated in the same way as BCL collections. This requires extending the Enumerator class which tracks the state of the enumeration. Other than iterating over a standard collection, examples include: Using ranges of numbers based on a...

ForEach() is defined on the List<T> class, but not on IQueryable<T> or IEnumerable<T>. You have two choices in those cases: ToList first The enumeration (or query) will be evaluated, copying the results into a new list or calling the database. The method is then called on each it...

Table Item The following class contains 2 properties a name (String) and the size (double). Both properties are wrapped in JavaFX properties to allow the TableView to observe changes. import javafx.beans.property.DoubleProperty; import javafx.beans.property.SimpleDoubleProperty; import javafx.be...

You can add an interpreter directive (shebang) to your script. Create a file called hello_world.rb which contains: #!/usr/bin/env ruby puts 'Hello World!' Give the script executable permissions. Here's how to do that in Unix: $ chmod u+x hello_world.rb Now you do not need to call the Ru...

By default, Django renders ForeignKey fields as a <select> input. This can cause pages to be load really slowly if you have thousands or tens of thousand entries in the referenced table. And even if you have only hundreds of entries, it is quite uncomfortable to look for a particular entry amo...

Differences in subsetting syntax A data.table is one of several two-dimensional data structures available in R, besides data.frame, matrix and (2D) array. All of these classes use a very similar but not identical syntax for subsetting, the A[rows, cols] schema. Consider the following data stored i...

LOOP AT itab INTO wa. ENDLOOP. FIELD-SYMBOLS <fs> LIKE LINE OF itab. LOOP AT itab ASSIGNING <fs>. ENDLOOP. LOOP AT itab ASSIGNING FIELD-SYMBOL(<fs>). ENDLOOP. LOOP AT itab REFERENCE INTO dref. ENDLOOP. LOOP AT itab TRANSPORTING NO FIELDS. ENDLOOP. Conditional L...

To make a custom pipe available application wide, During application bootstrap, extending PLATFORM_PIPES. import { bootstrap } from '@angular/platform-browser-dynamic'; import { provide, PLATFORM_PIPES } from '@angular/core'; import { AppComponent } from './app.component'; import { MyPipe }...

The semantics for this are similar to that of default value substitution, but instead of substituting a default value, it errors out with the provided error message. The forms are ${VARNAME?ERRMSG} and ${VARNAME:?ERRMSG}. The form with : will error our if the variable is unset or empty, whereas the ...

The process.env property returns an object containing the user environment. It returns an object like this one : { TERM: 'xterm-256color', SHELL: '/usr/local/bin/bash', USER: 'maciej', PATH: '~/.bin/:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin', PWD: '/Users/maciej', EDITOR: 'vi...

An iterable is an object that can return an iterator. Any object with state that has an __iter__ method and returns an iterator is an iterable. It may also be an object without state that implements a __getitem__ method. - The method can take indices (starting from zero) and raise an IndexError whe...

0-1 Knapsack The Knapsack Problem is a problem when given a set of items, each with a weight, a value and exactly 1 copy, determine the which item(s) to include in a collection so that the total weight is less than or equal to a given limit and the total value is as large as possible. C++ Exampl...

A view is most useful when it can be used to pull in data from more than one table. CREATE VIEW myview AS SELECT a.*, b.extra_data FROM main_table a LEFT OUTER JOIN other_table b ON a.id = b.id In mysql views are not materialized. If you now perform the simple query SELECT * FROM myview, my...

PHP 5.x5.4 When you build REST API's, you may need to reduce the information of an object to be passed to the client application. For this purpose, this example illustrates how to use the JsonSerialiazble interface. In this example, the class User actually extends a DB model object of a hypotetica...

In Index page change the following: error_reporting(E_ALL | E_STRICT); to error_reporting(E_ALL); Set $_SERVER['MAGE_IS_DEVELOPER_MODE'] = true and uncomment this line (remove the #) #ini_set('display_errors', 1); You can also Set Dev Mode using SetEnv in your .htaccess file To make th...

The use of Matlab Coder sometimes denies the use of some very common functions, if they are not compatible to C++. Relatively often there exist undocumented helper functions, which can be used as replacements. Here is a comprehensive list of supported functions.. And following a collection of alte...

During development, when certain code paths must be prevented from the reach of control flow, you may use assert(0) to indicate that such a condition is erroneous: switch (color) { case COLOR_RED: case COLOR_GREEN: case COLOR_BLUE: break; default: assert(0); ...