The grid can be configured with different strategies for loading row data into the grid, which are encapsulated into different Row Models. Changing which Row Model the grid is using means changing the strategy the grid is using for loading rows.
The grid comes with four row models:
The Client-Side Row Model deals with client-side data. The Server-Side, Infinite and Viewport Row Models deal with server-side data. The following is a summary of each:
This is the default. The grid will load all of the data into the grid in one go. The grid can then perform filtering, sorting, grouping, pivoting and aggregation all in memory.
This will present the data to the user and load more data as the user scrolls down. Use this if you want to display a large, flat (not grouped) list of data.
The Server-Side Row Model builds on the Infinite Row Model. In addition to lazy-loading the data as the user scrolls down, it also allows lazy-loading of grouped data with server-side grouping and aggregation. Advanced users will use Server-Side Row Model to do ad-hoc slice and dice of data with server-side aggregations.
The grid will inform the server exactly what data it is displaying (first and last row) and the server will provide data for exactly those rows only. Use this if you want the server to know exactly what the user is viewing, useful for updates in very large live datastreams where the server only sends updates to clients viewing the impacted rows.
Which row model you use is set as a grid property
rowModelType. Set it to one of
The default is
When to Use
Which row model you use will depend on your application. Here are some quick rules of thumb:
- If using ag-Grid Community, use Client-Side Row Model if you want to load all your data into the browser, or Infinite Row Model if you want to load it in blocks.
- If using ag-Grid Enterprise, use Client-Side Row Model if you want to load all your data into the browser, or Server-Side Row Model if you want to load it in blocks. Server-Side Row Model is Infinite Row Model plus more. So if you are an ag-Grid Enterprise customer, you should prefer Server-Side Row Model over Infinite Row Model.
- Don't use Viewport Row Model unless you understand what its advantages are and when you need them. We find many of our users use Viewport Row Model when they don't need to and end up with more complicated applications as a result.
Here are more detailed rules of thumb.
- If you are not sure, use default Client-Side. The grid can handle massive amounts of data (100k+ rows). The grid will only render what's visible on the screen (40 rows approximately, depending on your screen size) even if you have thousands of rows returned from your server. You will not kill the grid with too much data - rather your browser will run out of memory before the grid gets into problems. So if you are unsure, go with Client-Side Row Model first and only change if you need to. With Client-Side, you get sorting, filtering, grouping, pivoting and aggregation all done for you by the grid. All of the examples in the documentation use the Client-Side model unless specified otherwise.
- If you do not want to shift all the data from your server to your client, as the amount of data is too large to shift over the network or to extract from the underlying datasource, then use either Infinite, Server-Side or Viewport. Each one takes data from the server in different ways.
- Use Infinite or Server-Side to bring back a list of data one block at a time from the server. As the user scrolls, the grid will ask for more rows. Server-Side has more features than Infinite and will allow row grouping, aggregation, lazy-loading of groups and slice and dice of data.
- Use Viewport if you want the server to know exactly what the user is looking at. This is best when you have a large amount of changing data and want to push updates to the client when the server-side data changes. Knowing exactly what the user is looking at means you only have to push updates to the relevant users. All the row models can receive updates but only the Viewport row model provides the server with the information of the rows the users currently sees on screen without scrolling.
Row Model Comparisons
Below is a quick feature comparison of all the grid's features across all four row models.
|All Data in Client|
|Fetch Data as User Scrolls|
|Dynamic Row Height|
|Lazy Loading Row Groups|
|Header Checkbox Selection|
|Full Width Rows|
|CSV Export||(Data on screen)||(Data on screen)||(Data on screen)|
|Excel Export||(Data on screen)||(Data on screen)||(Data on screen)|
|Clipboard Copy & Paste|
|Update via Transaction||(Add Only)|
|Update via Async Transactions|
|Specify Selectable Rows|
Deeper Understanding of Row Models
The grid follows an MVC pattern. Each data item is wrapped in a Row Node and then stored in the Row Model. The grid rendering engine is called Row Renderer and listens for changes to the row model and updates the DOM accordingly.
Below shows a simplified version of a class diagram showing the relationships between the major classes involved with the row models.
The following should be noted from the diagram:
The grid has exactly one
RowRenderercontains a reference to the
PaginationProxywhere it asks for the rows one at a time for rendering.
The grid has exactly one
PaginationProxywill either a) do nothing if pagination is not active and just forward all requests to the Row Model or b) do pagination if pagination is active. The
PaginationProxyhas exactly one
You can configure the grid to use any of the provided Row Models - that's why
RowModelis in italics, it means it's an interface, the concrete implementation is what you decide when configuring the grid. The
RowModelcontains a list of
RowModelmay have a list of all the
RowNodes(Client-Side Row Model) or have a datasource where it can lazy-load
A RowNode has a reference to exactly one row data item (the client application provides
the row data items). The
RowNodehas state information about the row item, such as whether it is selected and the height of it.
When there is a change of state in the
RowModelfires a modelUpdated event which gets the
RowRendererto refresh. This happens for many reasons, or example the data is sorted, filtered, a group is opened, or the underlying data has changed.
Pagination can be applied to any of the row model types. The documentation on each row model type covers pagination for that row model type.
The Client-Side row model does not need a datasource. Infinite, Viewport and Server-Side all use a datasource. The documentation on each row model type explains how to configure the datasource for the particular row model.