9. A computer-readable storage medium encoded with instructions for controlling a computing device to forecast frequency of queries, the frequency of a query being a number of times the query is submitted during an interval, by a method comprising: for time-dependent queries, generating a time-dependent query model for the query to predict the frequency of the query at a future interval by analyzing internal factors of the query, the internal factors being derived from the frequency of the query during past intervals; for time-independent queries, generating a time-independent query model for the query to predict the frequency of the query at a future interval by analyzing both internal and external factors of the query, the external factors being derived from the frequency of another query during past intervals, wherein the generating of the time-independent query model includes identifying queries that are causally related to the query and the time-independent query model predicts frequency of the query based on the frequency of the causally related queries; predicting a frequency of a query during a future interval using the query model generated for the query; and displaying a graph of frequency of a query over time, the graph including an indication of the predicted frequency for the query.
9. A computer-readable storage medium encoded with instructions for controlling a computing device to forecast frequency of queries, the frequency of a query being a number of times the query is submitted during an interval, by a method comprising: for time-dependent queries, generating a time-dependent query model for the query to predict the frequency of the query at a future interval by analyzing internal factors of the query, the internal factors being derived from the frequency of the query during past intervals; for time-independent queries, generating a time-independent query model for the query to predict the frequency of the query at a future interval by analyzing both internal and external factors of the query, the external factors being derived from the frequency of another query during past intervals, wherein the generating of the time-independent query model includes identifying queries that are causally related to the query and the time-independent query model predicts frequency of the query based on the frequency of the causally related queries; predicting a frequency of a query during a future interval using the query model generated for the query; and displaying a graph of frequency of a query over time, the graph including an indication of the predicted frequency for the query. 10. The computer-readable storage medium of claim 9 wherein the generating of the query model includes: determining whether the query is time-dependent or time-independent.