Have you also taken a look at the online product documentation for these features? You may find this useful: http://onlinehelp.tableau.com/current/pro/desktop/en-us/help.htm#examples_teradata.html.
The Initial SQL setting is available for a few data sources and allows users to define a series of SQL statements which Tableau must issue immediately upon connecting to a database. This feature is not restricted to a single, specific use case. Instead you can use Initial SQL for operations such as the following:
- setting session attributes such as the transaction isolation level
- inserting records into a table that tracks when new connections are created
- creating and populating a session-scoped temporary table for on-the-fly ETL
Tableau will also issue Query Banding statements of the form SET QUERY_BAND=... at different times, depending on how the product is being used. After the connection is established Tableau will issue a query band statement to inform Teradata that Tableau will perform a number of metadata discovery options which may involve the system catalog. The Teradata DBA may set administrative rules to give queries priority in a low-latency queue when this query band is in effect, since this can greatly improve the initial connection experience in Tableau. After reading metadata but before issuing analytical queries, Tableau will issue another query band statement to inform Teradata that subsequent Tableau queries may be complex and operate on large amounts of data.
Aside from tuning for performance, a Teradata DBA can use query bands to enforce data security rules. Teradata doesn't have much documentation on how to use Query Banding for security, since the feature is actually quite general and powerful. However you may find this documentation useful: http://developer.teradata.com/database/articles/security-administration-accessing-the-teradata-database-through-a-middle-tier
I hope this helps,
We use Query Banding for Tableau Server to send user information to Teradata. When you connect to a published, live connection to Teradata using integrated authentication, the Tableau Server user is the one logging in. So, not matter who is connecting through Tableau Server, Teradata just sees 'Tableau Server'. By adding the query band PROXYUSER=<ServerUser>; Teradata can keep track of the actual user logged into Tableau Server. There are some settings on the Teradata server to enable this but it works well.
can you shed some light on this, as we are also trying to implement something of this sort
can we use query banding to pass user credentials to teradata?
Hi. I apologize for not seeing this sooner. If you still have questions about query-banding and Teradata please let me know.
I do have questions specific to Tableau connecting to Teradata with special security settings at Teradata end. Would greatly appreciate if you have some inputs
Hi Michael , any idea whether we can send in a setting in query band to close the connection for the proxy user after the data retrieval is done ?