Hi @rstu, I agree with Pawan that broadly it would be better if you could update your table component directly from your datasource rather than separately updating temporary data populating your table and your datasource. The latter opens up the potential for any number of issues with data integrity and isn't something I would recommend without a better sense of how this data is being updated and what other actions are being performed with the data in Retool.
That being said, you could populate a temporary state variable with the data from your initial query to your datastore. Then when the API request to update an individual row returns successfully, you could trigger a JS query that updates only the necessary slice of the temporary state with the state.setIn() method which would in turn update the table and avoid the expensive query run.
Something I might suggest instead would be to paginate the query that populates the table to avoid the expensive operation in the first place (assuming that your datastore supports pagination and that could work with your use case). Here's a link to our docs on server-side pagination if that could be an option!