Refreshing a lwc datatable after updating selected records from slds modal window is achieved using renderedCallback which is a callback method triggered at a specific phase of a component instance’s lifecycle.
@track props in renderedCallback() will result in an infinite loop. So In order to avoid infinite loop execution i used a boolean props to make sure this hook executed only once to perform one time operation(related records update logic in our scenario)
Next in that modal popup where user can able to select the account from Lookup input field(LDS utilised for showing the input field as lookup) for performing update operation. Also this example code contains lightning datatable column sorting and record id also embedded in contact record names for easy record navigation.
Git Repo link : https://github.com/dineshdk/Lightning-datatable