ALTER TABLE EMPLOYEES ADD pk_EmployeeID PRIMARY KEY (ID)
This will add a Primary key to the table Employees on the field ID. Including more than one column name in the parentheses along with ID will create a Composite Primary Key. When adding more than one column, the column names must be separat...
You can define implementation for specific instantiations of a template class/method.
For example if you have:
template <typename T>
T sqrt(T t) { /* Some generic implementation */ }
You can then write:
template<>
int sqrt<int>(int i) { /* Highly optimized integer implement...
$orderid = 12345;
$order = Mage::getModel('sales/order')->load($orderid);
The above code is roughly analogous to the following SQL query.
select * from sales_flat_order where entity_id=12345;
$incrementid = 100000000;
$order = Mage::getModel('sales/order')->loadByIncrementId($incrementid);
The above code is roughly analogous to the following SQL query.
select * from sales_flat_order where increment_id=100000000;
The increment_id is the customer facing order identifier, whereas...
Sort an enumeration in either ascending or descending order
Synonyms:
Sort-Object
sort
Assuming:
$names = @( "Aaron", "Aaron", "Bernie", "Charlie", "Danny" )
Ascending sort is the default:
$names | Sort-Object
$names | sort
Aaron
Aa...
You can group an enumeration based on an expression.
Synonyms:
Group-Object
group
Examples:
$names = @( "Aaron", "Albert", "Alphonse","Bernie", "Charlie", "Danny", "Ernie", "Frank")
$names | Group-Object -Prope...
Projecting an enumeration allows you to extract specific members of each object, to extract all the details, or to compute values for each object
Synonyms:
Select-Object
select
Selecting a subset of the properties:
$dir = dir "C:\MyFolder"
$dir | Select-Object Name, FullName, Att...
Class methods present alternate ways to build instances of classes. To illustrate, let's look at an example.
Let's suppose we have a relatively simple Person class:
class Person(object):
def __init__(self, first_name, last_name, age):
self.first_name = first_name
self.last...
This is a very common Exception. It causes your application to stop during the start or execution of your app. In the LogCat you see the message:
android.content.ActivityNotFoundException : Unable to find explicit activity class;
have you declared this activity in your AndroidManifest.xml?
In ...
The cx and cy values designate the location of the center of the circle.
The r attribute specifies the size of the radius of the circle.
<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<circle cx="40" cy="40&q...
class Car {
public position: number = 0;
private speed: number = 42;
move() {
this.position += this.speed;
}
}
In this example, we declare a simple class Car. The class has three members: a private property speed, a public property position and a public met...
class Car {
public position: number = 0;
protected speed: number = 42;
move() {
this.position += this.speed;
}
}
class SelfDrivingCar extends Car {
move() {
// start moving around :-)
super.move();
super.move();
}
}
...
Create a directory called ansible-helloworld-playbook
mkdir ansible-helloworld-playbook
Create a file hosts and add remote systems how want to manage. As ansible relies on ssh to connect the machines, you should make sure they are already accessible to you in ssh from your computer.
192.168.1.1...
public class Singleton {
private static final Singleton INSTANCE = new Singleton();
private Singleton() {}
public static Singleton getInstance() {
return INSTANCE;
}
}
It can be argued that this example is effectively lazy initialization. Section 12.4.1 of ...
To increment date objects in Javascript, we can usually do this:
var checkoutDate = new Date(); // Thu Jul 21 2016 10:05:13 GMT-0400 (EDT)
checkoutDate.setDate( checkoutDate.getDate() + 1 );
console.log(checkoutDate); // Fri Jul 22 2016 10:05:13 GMT-0400 (EDT)
It is possible to use setD...
To implement an item click listener and/or an item long click listener, you can create an interface in your adapter:
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> {
public interface OnItemClickListener {
void onItemSeleted(int position, Vi...
countMatches method from org.apache.commons.lang3.StringUtils is typically used to count occurences of a substring or character in a String:
import org.apache.commons.lang3.StringUtils;
String text = "One fish, two fish, red fish, blue fish";
// count occurrences of a substring
Str...
