extjs editor grid update rails

Question

i am trying to update records displayed in editor grid..but instead of updating same record, a new record gets inserted into the database...what am i missing??pllzz help..following is my JsonStore code :

Ext.data.Api.restActions = {
create  : 'POST',
read    : 'GET',
update  : 'PUT',
destroy : 'DELETE' };

ProdStore = Ext.extend(Ext.data.JsonStore, {
    constructor: function(cfg) {
        cfg = cfg || {};
        ProdStore.superclass.constructor.call(this, Ext.apply({
            storeId: 'ProdStore',
            id:'ProdStore',
            url: 'products.json',
            root: 'proddata',
            restful:true,
            idProperty:'id',
            successProperty:'success',
            autoLoad:true,
            autoSave:false,
            batch:true,
            writer: new Ext.data.JsonWriter({
            encode: false,
            listful: false,
            writeAllFields: false}),

            fields: [
                {   name:'customer_id'},{ name: 'prodnm'},
                {   name: 'qty'}, { name: 'rate' }, {   name: 'amt'}
            ]

        }, cfg));
    }
});
new ProdStore();

Answer 1

The idProperty set on the store should be the field that represents unique rows in the database. Perhaps customer_id in this case?

If this does not fix the issue, I would have to see the back end code to see how the save is being handled.