You can join two data sources
in the following ways:
- Dynamically using the JOIN command. The
join lasts for the duration of the session (or until you clear it
during the session) and creates a temporary view of the data that
includes all of the segments in both data sources. You can also use
the JOIN command to join two data sources of any type, including
a FOCUS data source to a non-FOCUS data source. The JOIN command
is described in detail in the Creating Reports With WebFOCUS Language manual.
- Statically within a Master File. This
method is helpful if you want to access the joined structure frequently.
The link (pointer) information needed to implement the join is permanently
stored and does not need to be retrieved for each record during
each request, saving you time. Like a dynamic Master File defined
join, it is always available and retrieves only the segments that
you specify. See Static Joins
Defined in the Master File: SEGTYPE = KU and KM. This is
supported for FOCUS data sources only.
- Dynamically within a Master File. This
method saves you the trouble of issuing the JOIN command every time
you need to join the data sources and gives you flexibility in choosing
the segments that will be available within the joined structure.
See Dynamic Joins Defined
in the Master File: SEGTYPE = DKU and DKM.
Tip: Some users find it helpful to prototype a database
design first using dynamic joins, implemented by issuing the JOIN
command or within the Master File. After the design is stable, to
change the frequently used joins to static joins defined in the
Master File, accelerating data source access. Static joins should
be used when the target or cross-referenced data source contents
do not change. You can change dynamic joins to static joins by using
the REBUILD facility.
Note: Master File defined joins are sometimes referred
to as cross-references.