Functional Indexes

This presentation will go over how to write functions that can be used to index fields. We receive faxes that are multi-page TIFF’s. The TIFF file name are called the raster id. We have data where we have the full path of the file name, the raster id and the raster id with page number.

Examples:
0000/000000
0000/0000001111
/studydata/studyname/0000/000000

We want to join across these fields quickly and this can be done with functional indexes, where the indexed value is not the data inside the field. In this case we will be indexing the value 0000/000000 from the above example.