Data in a table-structured file can be joined with data in other table-structured files, relational data, or nonrelational and unstructured data.
Using a wrapper, the federated server can process SQL statements
that query data in a table-structured file as if the data is contained in
an ordinary relational table or view.
How the federated server works with table-structured files is illustrated in the following figure.
For
example, the table-structured file DRUGDATA2.TXT is located
on a computer in your laboratory. The data in the file is:
556,DrugnameB,Manufacturer1 234,DrugnameA,Manufacturer2 721,DrugnameC,Manufacturer2
It is tedious to try to query and match this data with other tables from other data sources that you use.
After you register the DRUGDATA2.TXT file with the federated server, the table-structured file wrapper can access the data in the file as if the data is in a relational table.
For example, you can run the following query:
SELECT * FROM DRUGDATA2 ORDER BY DCODE
This query produces the following results:
| DCODE | DRUG | MANUFACTURER |
|---|---|---|
| 234 | DrugnameA | Manufacturer2 |
| 556 | DrugnameB | Manufacturer1 |
| 721 | DrugnameC | Manufacturer2 |
You can join the data in the DRUGDATA2.TXT file with data from other relational and nonrelational data sources and analyze all of the data together.
