10. The computer-readable storage medium of claim 8 wherein the code for generating the set of results based on the information related to the one or more e-mails comprises: code for receiving a first portion of the information in response to the first database query; code for receiving a second portion of the information in response to the second database query; and code for merging the first and second portions of the information to generate the set of results.
8. A computer-readable storage medium storing a set of code modules which when executed by a processor of a computer system cause the processor to search for e-mails, the computer-readable storage medium comprising: code for receiving information indicative of one or more search terms; code for determining a query plan based on the one or more search terms that specifies an interleaving between querying a first database in a plurality of databases that contains metadata associated with the e-mails and querying a second database in the plurality of databases that contains a full text index of the e-mails, the interleaving defining how results of a first database query against one database in the first or second databases influence a second database query against the other database in the first or second database; code for performing a search in response to the query plan to determine information related to the one or more e-mails; and code for generating a set of results based on the information related to the one or more e-mails.