1. A method comprising: determining a cost estimate for performing a first operation indicated in a first execution plan that is generated for a first query and that includes a plurality of operations; while executing the first execution plan, determining an actual cost of performing the first operation; determining a difference between the actual cost and the cost estimate; based on the difference, determining that the cost estimate is a misestimate; in response to determining that the cost estimate is a misestimate, storing object identification data that identifies one or more database objects that are associated with the first operation; after storing the object identification data, identifying, within a second execution plan that is generated for a second query that is different than the first query, a second operation that is associated with the one or more database objects; in response to identifying the second operation that is associated with the one or more database objects, analyzing the object identification data to determine that the one or more database objects are associated with a previous operation; determining, based on the object identification data, whether to ignore statistics that are available for the one or more database objects; wherein determining whether to ignore the statistics comprises determining a number of times a misestimate has been determined for the one or more database objects; and determining to ignore the statistics if the number of times a misestimate has been determined for the one or more database objects is greater than a particular threshold number; wherein the method is performed by one or more computing devices.