Getting Started

Basics

Query Modifiers

.where() .sort()

Query Predicates

.equals() .notEquals() .exists() .notExists() .startsWith() .endsWith() .contains() .greaterThan() .lessThan() .between() .outside()

Query Executors

.read() .first() .last() .count() .sum() .average() .min() .max() .update() .delete()

Login Methods

.exists() .login() .logout()

Instance Methods

.read() .delete()

Instance Login Methods

.login() .logout() .changePassword()

Misc

Back.then() Back.saved() Back.user() Back.eachProperty() Back.eachDescendant() IFile Property LoginResult

Executors.sum()

Executes the query, returning only the sum of the values of the specified property, of all matched results.

// With no filters:
Employees.sum(Employee.salary, sum =>
{
	// sum is the sum of the salaries of all Employee objects
});

// With a filter:
Employees
	.where(Employee.name).equals("Paul")
	.sum(Employee.salary, sum =>
	{
		// sum is the sum of all the salaries of employees named "Paul".
	});

Method signature (TypeScript)

static sum(property: NumberProperty, resultFn: (result: number) => void): void;

Details

property
A NumberProperty to apply the sum operation against.
resultsFn
The function that will be called when the query has returned. A number is passed to the first parameter.
returns
void