When using
conventional processing to access data inside a Teradata Enterprise
Data Warehouse (EDW), SAS Enterprise Miner asks the
SAS/ACCESS engine
for all rows of the table being processed. The
SAS/ACCESS engine generates
an SQL SELECT * statement that is passed to the Teradata EDW. That
SELECT statement fetches all the rows in the table, and the
SAS/ACCESS
engine returns them to SAS Enterprise Miner. As the number of rows
in the table grows over time, network latency grows because the amount
of data that is fetched from the Teradata EDW to the SAS scoring process
increases.
The SAS
Scoring Accelerator for Teradata embeds the robustness of SAS Enterprise
Miner scoring models directly in the highly scalable Teradata database.
By using the SAS In-Database technology and the SAS Scoring Accelerator
for Teradata, the scoring process is done inside the data warehouse,
and thus does not require the transfer of data.
The SAS
Scoring Accelerator for Teradata takes the models that are developed
by SAS Enterprise Miner and translates them into scoring functions
that can be deployed inside Teradata. After the scoring functions
are published, the functions extend the Teradata SQL language and
can be used in SQL statements like other Teradata functions.
The SAS Scoring
Accelerator for Teradata consists of two components:
-
the Score
Code Export node in SAS Enterprise Miner. This extension exports the
model scoring logic, including metadata about the required input and
output variables, from SAS Enterprise Miner.
-
the publishing client that includes the %INDTD_PUBLISH_MODEL
macro. This macro translates the scoring model into .c and .h files
for creating the scoring functions and generates a script of Teradata
commands for registering the scoring functions. The publishing client
then uses the
SAS/ACCESS Interface to Teradata to publish the scoring
functions to Teradata.