ImmutableService requires getRowNodeId() callback to be implemented, your row data need IDs

Question

I tried to add

[deltaRowDataMode]="true"

to my grid and called

this.gridApi.setRowData(this.rowData);

but the code throws the error

ag-Grid: ImmutableService requires getRowNodeId() callback to be implemented, your row data need IDs!

push../projects/secdo-infra-lib/node_modules/ag-grid-community/dist/lib/rowModels/clientSide/immutableService.js.ImmutableService.createTransactionForRowData @ immutableService.js:38 push../projects/secdo-infra-lib/node_modules/ag-grid-community/dist/lib/gridApi.js.GridApi.setRowData @ gridApi.js:151

Looking this up online I have read that getRowNodeId is auto generated if not set so I don't understand why the error is thrown.

Answer 1

From the docs

For the deltaRowDataMode to work, you must be providing ID's for the row nodes by implementing the getRowNodeId() callback.

The grid works out the delta changes with the following rules:

IF the ID for the new item doesn't have a corresponding item already in the grid THEN it's an 'add'.
IF the ID for the new item does have a corresponding item in the grid THEN compare the object references. If the object references are different, it's an update, otherwise it's nothing (excluded from the transaction).
IF there are items in the grid for which there are no corresponding items in the new data, THEN it's a 'remove'.

You can implement getRowNodeId() in a way that it returns unique ids for each row. e.g.

this.getRowNodeId = function(data) {
  return data.id; //id is a field here
};

This official example has more details