Tutorial by Examples: l

This code selects data out of a table and displays it in the query tool (usually SSMS) SELECT Column1, Column2, Column3 FROM MySourceTable; This code inserts that data into a table: INSERT INTO MyTargetTable (Column1, Column2, Column3) SELECT Column1, Column2, Column3 FROM MySourceTable;
This code selects data out of a table: SELECT Column1, Column2, Column3 FROM MySourceTable; This code creates a new table called MyNewTable and puts that data into it SELECT Column1, Column2, Column3 INTO MyNewTable FROM MySourceTable;
To move data you first insert it into the target, then delete whatever you inserted from the source table. This is not a normal SQL operation but it may be enlightening What did you insert? Normally in databases you need to have one or more columns that you can use to uniquely identify rows so we w...
Since C# 6.0 exceptions can be filtered using the when operator. This is similar to using a simple if but does not unwind the stack if the condition inside the when is not met. Example try { // ... } catch (Exception e) when (e.InnerException != null) // Any condition can go in here. { ...
Example is the main part of Documentation, it is thus important to provide clear and useful examples. Good examples are self-contained and succinct. Examples usually would have code for users to understand the topic better. Refer to the Help Center for more information.
Within a catch block the throw keyword can be used on its own, without specifying an exception value, to rethrow the exception which was just caught. Rethrowing an exception allows the original exception to continue up the exception handling chain, preserving its call stack or associated data: try...
@Provider public class CORSResponseFilter implements ContainerResponseFilter { public void filter( ContainerRequestContext requestContext, ContainerResponseContext responseContext ) throws IOException { MultivaluedMap<String, Object> headers = responseCo...
The display CSS property is fundamental for controlling the layout and flow of an HTML document. Most elements have a default display value of either block or inline (though some elements have other default values). Inline An inline element occupies only as much width as necessary. It stacks horiz...
SRXMPPDemo Download the example and all the classes here - https://github.com/SahebRoy92/SRXMPPDemo A demo on XMPP in Objective C, with various simple and complex features implemented in it. All the features of XMPP is done by "in band" xmpp functions. Few features this project contains...
Slices are the typical way go programmers store lists of data. To declare a slice variable use the []Type syntax. var a []int To declare and initialize a slice variable in one line use the []Type{values} syntax. var a []int = []int{3, 1, 4, 1, 5, 9} Another way to initialize a slice is with...
A class designed to be inherited-from is called a Base class. Care should be taken with the special member functions of such a class. A class designed to be used polymorphically at run-time (through a pointer to the base class) should declare the destructor virtual. This allows the derived parts of...
Bear in mind that declaring a destructor inhibits the compiler from generating implicit move constructors and move assignment operators. If you declare a destructor, remember to also add appropriate definitions for the move operations. Furthermore, declaring move operations will suppress the genera...
When creating a recyclerview with a gridlayout layout manager you have to specify the span count in the constructor. Span count refers to the number of columns. This is fairly clunky and doesn't take into account larger screen sizes or screen orientation. One approach is to create multiple layouts f...
To add a header to a recyclerview with a gridlayout, first the adapter needs to be told that the header view is the first position - rather than the standard cell used for the content. Next, the layout manager must be told that the first position should have a span equal to the *span count of the e...
Using the Array::new constructor, your can initialize an array with a given size and a new array in each of its slots. The inner arrays can also be given a size and and initial value. For instance, to create a 3x4 array of zeros: array = Array.new(3) { Array.new(4) { 0 } } The array generated a...
Define your class that will represent your custom error. public class ErrorDto { public int Code { get; set; } public string Message { get; set; } // other fields public override string ToString() { return JsonConvert.SerializeObject(this); } } Then put nex...
The idea is to use HttpContext.Response.OnStarting callback, as this is the last event that is fired before the headers are sent. Add the following to your middleware Invoke method. public async Task Invoke(HttpContext context) { context.Response.OnStarting((state) => { if ...
A shell script is a very versatile way to extend your build to basically anything you can think of. As an exmaple, here is a simple script to compile protobuf files and add the result java files to the source directory for further compilation: def compilePb() { exec { // NOTICE: grad...
With the rgdal package it is possible to import and export shapfiles with R. The function readOGR can be used to imports shapfiles. If you want to import a file from e.g. ArcGIS the first argument dsn is the path to the folder which contains the shapefile. layer is the name of the shapefile without...
The packages foreign and haven can be used to import and export files from a variety of other statistical packages like Stata, SPSS and SAS and related software. There is a read function for each of the supported data types to import the files. # loading the packages library(foreign) library(have...

Page 115 of 861