1. A computer-implemented method of storing multiple fields for multiple tenants in a single multi-tenant data structure, comprising: defining a multi-tenant data structure having a plurality of data columns and one or more index columns; defining a first data field for a first tenant, said first field having a first data type; defining a second data field for a second tenant, said second field having a second data type, wherein the second data type is different than said first data type; when records having data values in the first and second fields are created by the first and second tenants, storing the data values of first and second fields to a single column in the data structure, wherein the single column includes data values having different data types for different tenants; and copying to a first one of the index columns the data values stored in the single data column for the first field in response to a request from the first tenant to index data in the first data field.