1. A computer-implemented method of improving a query that is to be performed in the context of a tenant-specific filter on a tenant identifier, the method comprising: receiving at a network interface of a server an original query, wherein the original query is associated with data within a database as identified by the tenant identifier, and wherein the database includes at least a first index and a second index, further wherein the database stores data for multiple tenants that are unrelated organizations and have different database schemas, the data corresponding to each tenant having tenant-specific characteristics; retrieving, using a processor of the server, metadata associated with the data, wherein at least a portion of the data is stored in a common table within the database system; determining, using the processor, a tenant-selective query syntax by analyzing at least metadata generated from tenant-specific characteristics; analyzing, using the processor, metadata generated from information about the organization to which the original query corresponds; and generating, using the processor, an improved query using the query syntax, wherein the improved query is based at least in part upon the original query and a result of a join between a first number of rows associated with the first index and a second number of rows associated with the second index and the analysis of the metadata.