Stay in sync - Introducing Teradata Unity 13.10

Unity
Unity is Teradata’s data synchronization and workload routing tool providing Active – Active database availability delivering near real-time RTO/RPO
Teradata Employee

Re: Stay in sync - Introducing Teradata Unity 13.10

Ericsun2 -

Thanks for your interest in future releases of Unity Director and Unity Loader 14.00. (new names)  I've just published a new article regarding the 14.00 release.  http://developer.teradata.com/ecosystem/articles/unity-director-14-00-unity-loader-14-00-now-availab...  In the article I explain the content in Unity Director 14.00 (formerly Unity 13.10) and Unity Loader 14.00 (Bulk Loads).  With the advent of Unity Loader 14.00, we now fully support TPT Load and JDBC Fastload.  TPT Update is planned for a future release. 

Teradata Employee

Re: Stay in sync - Introducing Teradata Unity 13.10

Abraham -

Unity Director and Unity Loader require a dedicated Managed Servers.  There is no software-only option.  The Managed Servers are pre-configured and pre-statged with the software to make it easy for customers.  This also allows us to provide a single-vendor (Hardware and Software) support model for the offering.   We have specifically configured the Managed Server to enable the failover, high availability, and recovery scenarios that Unity Director and Unity Loader provide.    

Enthusiast

Re: Stay in sync - Introducing Teradata Unity 13.10

Jeff,

Curios on how exactly the replication works? Assuming I am generating a surrogate Key in my system A using ROWID or something similar and replicating the value to system B. Would replication try to execute the "Same SQL" I am running on System A to generate the key on System B? In this case would replication fail as we are having two different values?

In brief I am trying to understand if replication is going to "Exceute the SQL Statement" Or "Copy the Data Over"

If it "Exceute the SQL Statements", then when designing Active/Active systems using Unity do we need be cautios of how and where we generate key?

Appreciate your response on this

Thanks,

Sai

Teradata Employee

Re: Stay in sync - Introducing Teradata Unity 13.10

Sai - 

With Unity Director,  we try to not to use the word "replication" because it connotes creation on one system and copy to another. Instead, we use the term "synchronization" in an attempt to avoid this confusion. To answer your question directly, your assumption about the “Same SQL” being sent to both systems is correct and the product will not “copy the data over”. 

Regarding surrogate keys: Since it has the potential to generate different values, when a SQL statement submitted through Unity Director is used to insert row(s) into a table that contains an IDENTITY column, Unity Director will reject the request. Instead, we recommend that the surrogate key be generated either outside the database (i.e. in the ETL server) or by using a deterministic mechanism such as a ROW_NUMBER() calculation that has a deterministic ORDER BY clause.

That said, we do plan to add support for IDENTITY columns in a future releaese of the Unity Director product but this is not in the short term.

Enthusiast

Re: Stay in sync - Introducing Teradata Unity 13.10

Thanks Jeff for the great explanation. Wanted to confirm on this as this is crucial when designing an Active/Active system.

Thanks again!

Enthusiast

Re: Stay in sync - Introducing Teradata Unity 13.10

Hi All, 

Could you please tell me how Identity Columns will be sync in mulitple system ?

which mode we need to use ?

Thanks,

Mono

Highlighted
Teradata Employee

Re: Stay in sync - Introducing Teradata Unity 13.10

Identity Columns are not supported in any Unity Director release. The reason is that the generation of the value is non-deterministic and will result in different values if you run it on two different systems. Unity Director requires the tables to be identical, even the Identy Column. This is a future roadmap consideration.

Regards,

Cliff