1. A method of using an index shared between a plurality of tables to access a data sharing space (DSS) storing a set of rows from a base table having a plurality of rows with stored data, the method comprising: identifying, in response to a first query for a first table of the plurality of tables, first data values of the index; retrieving, using index elements corresponding to the first data values, a first subset of the set of rows from the DSS; identifying, in response to a second query for a second table of the plurality of tables, second data values and at least some of the first data values of the index; retrieving, using the index elements corresponding to the second data values and the at least some of the first data values, a second subset of the set of rows from the DSS; identifying a first set of individual binary bit values using the first query; indicating the first data values based on the first set of individual binary bit values are included in the first table; identifying a second set of individual binary bit values using the second query; indicating the second data values and the at least some of the first data values based on the second set of individual binary bit values are included in the second table; and applying the second query to the second subset of the set of rows.