7. A system for generating a graphical representation of a query optimization process, comprising: a memory configured to store modules comprising: a parsing module configured to parse a search space log, the log comprising an order in time in which one or more access plans were evaluated, a property for an object of one of the one or more evaluated access plans, and a best access plan selected from the one or more evaluated access plans, a presenting module configured to present the one or more evaluated access plans on a time axis and a cost axis of a timeline, organized on the timeline corresponding to the order in time in which the one or more evaluated access plans were evaluated, an identifying module configured to identify the best access plan on the timeline, and a displaying module configured to display a graphical representation of the time axis and the cost axis; and one or more processors configured to process the modules.
7. A system for generating a graphical representation of a query optimization process, comprising: a memory configured to store modules comprising: a parsing module configured to parse a search space log, the log comprising an order in time in which one or more access plans were evaluated, a property for an object of one of the one or more evaluated access plans, and a best access plan selected from the one or more evaluated access plans, a presenting module configured to present the one or more evaluated access plans on a time axis and a cost axis of a timeline, organized on the timeline corresponding to the order in time in which the one or more evaluated access plans were evaluated, an identifying module configured to identify the best access plan on the timeline, and a displaying module configured to display a graphical representation of the time axis and the cost axis; and one or more processors configured to process the modules. 11. The system of claim 7 , further comprising: a comparing module to compare the graphical representation of the timeline to a second graphical representation of a second timeline, the second timeline corresponding to a second search space log.