VisFlow works with heterogeneous data by linking. Essentially, linking relates two heterogeneous tables by defining a key value shared between the two tables. Each table must have a column that contains the keys. Linking can be achieved using a Linker.
To link two heterogenous tables
T2, one column must be chosen from the two tables as the shared key column.
The corresponding rows in the two tables must have an equal value in the key column.
The key values are extracted from
T1 and used to filter data items from
For example, assume
T1 contains the mpg values of the cars:
T2 contains the sales number of the cars:
|car name||sales number|
The shared key column is name from
T1 and car name from
If we want to find the sales numbers for a subset of cars from
T1, we can extract the name values of the
T1 subset into a list of constants, and then use these constants to filter and find the data items in
T2 that match these car names.
We can use a Linker
T1and Filter Column to car name from