Missing index on device_graphs

On our instance this table has about 112,000 rows. Every time queries for the device graphs were causing a scan of the table.

Check out the before and after. Adding the index lowered the number of rows scanned from 112K to 15.

SELECT `graph` FROM `device_graphs` WHERE `device_id` = '2745';

create index device_graphs_device_id ON device_graphs(device_id);