Say you have a simple Ext store:

var myStore = new Ext.data.Store({
  url:    '/widgets.json',
  reader: someReader
});

var myStore = new Ext.data.Store({
  url:    '/widgets.json',
  reader: someReader
});

Which you put in a grid, along with a paging toolbar:

var myGrid = new Ext.grid.GridPanel({
  store:   myStore,
  columns: [.....],
  bbar:    new Ext.PagingToolbar({
    store: myStore
  })
  ... etc ...
});

var myGrid = new Ext.grid.GridPanel({
  store:   myStore,
  columns: [.....],
  bbar:    new Ext.PagingToolbar({
    store: myStore
  })
  ... etc ...
});

Your grid loads up and the store performs a GET request to /widgets.json, which returns your widgets along with a total (see an example).

Awesome, but now we click one of the paging buttons on the PagingToolbar and we have a problem - our request has turned into POST /widgets.json, with "start=20" and "limit=20" as POST params.

Now we don't really want that - we're not POSTing any data to the server after all, we're just trying to GET some. If you're using a nice RESTful API on your server side this may cause you a real problem, as POST /widgets will likely be taken as an attempt to create a new Widget.

Luckily, as with most things the solution is simple if you know how. An Ext.data.Store delegates loading its data off to an Ext.data.DataProxy subclass. By default your store will create an Ext.data.HttpProxy using the url: '/widgets.json' you passed in your store config. To make sure your stores are always requesting data using GET, just provide a proxy like this:

var myStore = new Ext.data.Store({
  proxy: new Ext.data.HttpProxy({
    url:    '/widgets.json',
    method: 'GET'
  }),
  reader: someReader
});

var myStore = new Ext.data.Store({
  proxy: new Ext.data.HttpProxy({
    url:    '/widgets.json',
    method: 'GET'
  }),
  reader: someReader
});