1. A method comprising: receiving a first query that specifies a first object identifier; and if a first query plan exists that implements the first query, except that the first query plan does not comprise the first object identifier and instead comprises a parameter marker in place of the first object identifier, creating a first query execution plan from the first query plan, substituting the first object identifier in the first query execution plan for the parameter marker, and executing the first query execution plan to read a first object identified by the first object identifier.