apply(callback, params, async)

domain: client

language: javascript

class Item class


Sends all updated, inserted, and deleted records from the item dataset to the application server for writing to the database.

The apply method can have the following parameters:

  • callback: if the parameter is not present and async parameter is false or undefined, the request to the server is sent synchronously, otherwise, the request is executed asynchronously and after the response is received, the callback is executed

  • params - an object specifying user defined params, that can be used on the server in the on_apply event handler for some additional processing

  • async: if its value is true, and callback parameter is missing, the request is executed asynchronously

The order of parameters doesn’t matter.

The apply method

  • checks whether the item is a detail, and if it is, returns (the master saves the details changes)

  • checks whether the item is in edit or insert state , and if so, posts the record

  • checks if the change log has changes, and if not, executes callback if it is passed and then returns

  • triggers the on_before_apply event handler if one is defined for the item

  • sends changes to the server

  • server on receiving the request checks whether on_apply event handler is defined for the item, and if it is, executes it, otherwise generates and executes SQL query to write changes to the database, see also on_apply events topic

  • when generating an SQL query, checks whether a user, that send the request, has rights to make these changes, if not raises an exception

  • writes changes to the database

  • after writing changes to the database, server sends to the client results of the execution

  • if exception was raised during the operation on the server the client throws an exception, before throwing exception, if the callback parameter is passed, it is called and the error is passed as the callback function parameter

  • the client, based on the results, updates the change log

  • triggers the on_after_apply event handler if one is defined for the item

  • if the callback parameter is passed, it is called.


The server, before writing new records to the database table, generates values for the primary fields. The client updates these fields, based on information received from the server. If you change values of some other fields in the on_apply event handler, these changes will not be reflected on the client. You can update them yourself using, for example, refresh_record method


var self = this;
this.apply(function(err) {
    if (err) {
    else {
        //some code to execute after appling changes

See also

Modifying datasets