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Outer joins return all the rows from one or both tables, plus matching rows. Table People PersonID FirstName 1 Alice 2 Bob 3 Eve Table Scores PersonID Subject Score 1 Math 100 2 Math 54 2 Science 98 Left joining the tables: Select * f...

This simple function will execute the specified Select SQL command and return the result as data set. Public Function ReadFromDatabase(ByVal DBConnectionString As String, ByVal SQL As String) As DataTable Dim dtReturn As New DataTable Try 'Open the connection using the connection...

Using the /p switch with the SET command you can define variables from an Input. This input can be a user Input (keyboard) : echo Enter your name : set /p name= echo Your name is %name% Which can be simplified like this : set /p name=Enter your name : echo Your name is %name% Or you can...

GSON does not support inheritance our of the box. Let's say we have the following class hierarchy: public class BaseClass { int a; public int getInt() { return a; } } public class DerivedClass1 extends BaseClass { int b; @Override public int getIn...

libraryDependency is the SettingKey that handles 'managed' library dependencies, which are dependencies that are automatically downloaded, matching the supplied versions. To add a single dependency: libraryDependencies += "com.typesafe.slick" %% "slick" % "3.2.0-M1" ...

Let's assume we have an entity status field with 3 options Tentative Pending Approved Our goal is to show different color for each status as follow: Tentative will be Red Pending will be Orange Approved will be Green The switch condition: =Switch(Fields!ItemStatus.Value = "Tentativ...

Q. Why we need compilation? Ans. We need compilation for achieving higher level of efficiency of our Angular applications. Take a look at the following example, // ... compile: function (el, scope) { var dirs = this._getElDirectives(el); var dir; var scopeCreated; dirs.forEach(functi...

Sometimes a complex IF condition is needed. Let's take and example, Assuming we have the following raw data: ItemIDItem NameItem Status1Item 1Tentative1Item 1Pending1Item 1Approved The Goal is: Let's assume our business user ask to see which items are not approved and which are approved. Tentati...

pipes's core data type is the Proxy monad transformer. Pipe, Producer, Consumer and so on are defined in terms of Proxy. Since Proxy is a monad transformer, definitions of Pipes take the form of monadic scripts which await and yield values, additionally performing effects from the base monad m.

Unsafe is stored as a private field that cannot be accessed directly. The constructor is private and the only method to access public static Unsafe getUnsafe() has privileged access. By use of reflection, there is a work-around to make private fields accessible: public static final Unsafe UNSAFE; ...

$perl -d:MOD script.pl runs the program under the control of a debugging, profiling, or tracing module installed as Devel::MOD. For example, -d:NYTProf executes the program using the Devel::NYTProf profiler. See all available Devel modules here Recommended modules: Devel::NYTProf -- Powerful ...

If you want to instantiate an instance of user control inside ASPX code behind page, you need to write user control declaration on Page_Load event as follows: public partial class Default : System.Web.UI.Page { protected void Page_Load(Object sender, EventArgs e) { Control contr...

socket_last_error can be used to get the error ID of the last error from the sockets extension. socket_strerror can be used to convert the ID to human-readable strings. function onSocketFailure(string $message, $socket = null) { if(is_resource($socket)) { $message .= ": " ....

Import Element Tree module import xml.etree.ElementTree as ET Element() function is used to create XML elements p=ET.Element('parent') SubElement() function used to create sub-elements to a give element c = ET.SubElement(p, 'child1') dump() function is used to dump xml elements. ET.dump...

Actions are located in /usr/local/etc/scanbd/scanbd.conf. I have 4 buttons that are scan, copy, email and file. The default config file doesn't include all actions per default, you will probably have to add the block manually. You can have less or more buttons depending of your scanner model. ...

For the current shell, this takes you to the previous directory that you were in, no matter where it was. cd - Doing it multiple times effectively "toggles" you being in the current directory or the previous one.

The default directory is the home directory ($HOME, typically /home/username), so cd without any directory takes you there cd Or you could be more explicit: cd $HOME A shortcut for the home directory is ~, so that could be used as well. cd ~

GRANT SELECT ON [dbo].[someTable] TO [aUser]; REVOKE SELECT ON [dbo].[someTable] TO [aUser]; --REVOKE SELECT [dbo].[someTable] FROM [aUser]; is equivalent DENY SELECT ON [dbo].[someTable] TO [aUser];

-- SQL 2005+ exec sp_addrolemember @rolename = 'myRole', @membername = 'aUser'; exec sp_droprolemember @rolename = 'myRole', @membername = 'aUser'; -- SQL 2008+ ALTER ROLE [myRole] ADD MEMBER [aUser]; ALTER ROLE [myRole] DROP MEMBER [aUser]; Note: role members can be any database-level pri...

In this example we have a service, let's call it search service that has a method called search() which will initiate a get request to a back end API. function SearchService($http) { const service = {}; service.search = function() { return $http({method: 'GET', url: `/api/s...