# Editor example Join tables - working with multiple SQL tables

Data in relational databases is often stored over multiple tables, partitioned by the data type and then joined together using SQL JOIN queries. Editor makes working with multiple tables super easy through its, and DataTables', ability to work with nested Javascript objects. Additional the PHP libraries `leftJoin()` method make working with joins on the server-side just as easy as on the client-side - see the PHP join documentation for further information on the library options.

This example shows the simplest, but also most common, use case for joined data - a foreign reference key, pointing to another record. In this case the users database table has a column called site which is a reference to the sites database table. Using the `leftJoin()` PHP method in Editor server-side classes, the returned data structure for each row looks like:

    {
    	"DT_RowId": "row_1",
    	"users": {
    		"first_name": "Quynn",
    		"last_name": "Contreras",
    		"phone": "1-971-977-4681",
    		"site": "1"
    	},
    	"sites": {
    		"name": "Edinburgh"
    	}
    }

To display these fields in DataTables we use the `columns.dataDT` option to access the nested data - for example `users.first_name` (using dotted Javascript object notation).

On create, edit and remove Editor will also update the database accordingly for these actions automatically. With Editor, editing joined tables takes seconds to configure saving you a huge amount of time.

First name | Last name | Phone # | Location
--- | --- | --- | ---
First name | Last name | Phone # | Location

- Javascript
- HTML
- CSS
- Ajax
- Server-side script

The Javascript shown below is used to initialise the table shown in this example:

`var editor; // use a global for the submit and return data rendering in the examples $(document).ready(function() { editor = new $.fn.dataTable.Editor( { ajax: "../php/join.php", table: "#example", fields: [ { label: "First name:", name: "users.first_name" }, { label: "Last name:", name: "users.last_name" }, { label: "Phone #:", name: "users.phone" }, { label: "Site:", name: "users.site", type: "select" } ] } ); $('#example').dataTable( { dom: "Tfrtip", ajax: { url: "../php/join.php", type: 'POST' }, columns: [ { data: "users.first_name" }, { data: "users.last_name" }, { data: "users.phone" }, { data: "sites.name" } ], tableTools: { sRowSelect: "os", aButtons: [ { sExtends: "editor_create", editor: editor }, { sExtends: "editor_edit", editor: editor }, { sExtends: "editor_remove", editor: editor } ] }, initComplete: function ( settings, json ) { // Populate the site select list with the data available in the // database on load editor.field( 'users.site' ).update( json.sites ); } } ); } );`

In addition to the above code, the following Javascript library files are loaded for use in this example:

- ../../../../media/js/jquery.js
- ../../../../media/js/jquery.dataTables.js
- ../../../TableTools/js/dataTables.tableTools.js
- ../../js/dataTables.editor.js

The HTML shown below is the raw HTML table element, before it has been enhanced by DataTables:

This example uses a little bit of additional CSS beyond what is loaded from the library files (below), in order to correctly display the table. The additional CSS used is shown below:

``

The following CSS library files are loaded for use in this example to provide the styling of the table:

- ../../../../media/css/jquery.dataTables.css
- ../../../TableTools/css/dataTables.tableTools.css
- ../../css/dataTables.editor.css

This table loads data by Ajax. The latest data that has been loaded is shown below. This data will update automatically as any additional data is loaded.

The script used to perform the server-side processing for this table is shown below. Please note that this is just an example script using PHP. Server-side processing scripts can be written in any language, using the protocol described in the DataTables documentation.