You can use spatial functions to generate spatial data
from input data.
For example, suppose that the bank whose branches are defined in
the BRANCHES table wants to know how many customers are located within
five miles of each branch. Before the bank can obtain this information
from the database, it needs to define the zone that lies within a
specified radius around each branch. An IBM® Spatial Support for Db2 for z/OS® function,
ST_Buffer, can create such a definition. Using the coordinates of
each branch as input, ST_Buffer can generate the coordinates that
demarcate the perimeters of the zones. The following figure shows
the BRANCHES table with information that is supplied by ST_Buffer.Figure 1. Table that includes new spatial data derived from existing spatial data. The coordinates in the SALES_AREA column were derived by the ST_Buffer function from the coordinates in the LOCATION column. Like the coordinates in the LOCATION column, those in the SALES_AREA column are simulated; they are not actual.
In addition to the ST_Buffer function, IBM Spatial Support for Db2 for z/OS provides
several other functions that derive new spatial data from existing
spatial data.
