Syntax:
SELECT *
FROM table_name
Using the asterisk operator * serves as a shortcut for selecting all the columns in the table. All rows will also be selected because this SELECT statement does not have a WHERE clause, to specify any filtering criteria.
This would also work the same way if you...
The function std::find, defined in the <algorithm> header, can be used to find an element in a std::vector.
std::find uses the operator== to compare elements for equality. It returns an iterator to the first element in the range that compares equal to the value.
If the element in question is...
An array can easily be converted into a std::vector by using std::begin and std::end:
C++11
int values[5] = { 1, 2, 3, 4, 5 }; // source array
std::vector<int> v(std::begin(values), std::end(values)); // copy array to new vector
for(auto &x: v)
std::cout << x << &q...
At first glance it may appear that null and undefined are basically the same, however there are subtle but important differences.
undefined is the absence of a value in the compiler, because where it should be a value, there hasn't been put one, like the case of an unassigned variable.
undefined...
1 / 0; // Infinity
// Wait! WHAAAT?
Infinity is a property of the global object (therefore a global variable) that represents mathematical infinity. It is a reference to Number.POSITIVE_INFINITY
It is greater than any other value, and you can get it by dividing by 0 or by evaluating the express...
When local changes are present, the git pull command aborts reporting :
error: Your local changes to the following files would be overwritten
by merge
In order to update (like svn update did with subversion), you can run :
git stash
git pull --rebase
git stash pop
A convenient way coul...
NaN stands for "Not a Number." When a mathematical function or operation in JavaScript cannot return a specific number, it returns the value NaN instead.
It is a property of the global object, and a reference to Number.NaN
window.hasOwnProperty('NaN'); // true
NaN; // NaN
Perhaps con...
Reachability uses NSNotification messages to alert observers when the network state has changed. Your class will need to become an observer.
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];
Elsewher...
Many IDEs provide support for generating HTML from Javadocs automatically; some build tools (Maven and Gradle, for example) also have plugins that can handle the HTML creation.
However, these tools are not required to generate the Javadoc HTML; this can be done using the command line javadoc tool.
...
This example demonstrates how Angular expressions are evaluated when using type="text" and type="number" for the input element.
Consider the following controller and view:
Controller
var app = angular.module('app', []);
app.controller('ctrl', function($scope) {
$sco...
django-admin is a command line tool that ships with Django. It comes with several useful commands for getting started with and managing a Django project.
The command is the same as ./manage.py , with the difference that you don't need to be in the project directory. The DJANGO_SETTINGS_MODULE envir...
// Java:
String joined = things.stream()
.map(Object::toString)
.collect(Collectors.joining(", "));
// Kotlin:
val joined = things.joinToString() // ", " is used as separator, by default
Once you have a Dockerfile, you can build an image from it using docker build.
The basic form of this command is:
docker build -t image-name path
If your Dockerfile isn't named Dockerfile, you can use the -f flag to give the name of the Dockerfile to build.
docker build -t image-name -f Dockerfi...
Templates can be previewed and edited using the Rule Editor tab in Bosun. Use the Jump to links to select the alert you want to edit, then you can use the template button next to macro to switch between the alert an template sections of the configuration. If an alert has multiple instances you can u...
You can embed another template body into your template via {{template "mysharedtemplate" .}} to reuse shared components. Here is an example that creates a header template that can be reused at the top of all other template bodies. It also uses CSS to stylize the output so that it is easier...
