VantageCloud Lake embeds intelligence in the Primary Cluster‘s Optimiser to route the query steps between the Primary Cluster and the Compute Clusters. As a result, Lake can leverage the maximum potential of its architecture when executing the workload.

Specifically, the Global Planner directs the work to run in the appropriate cluster. Remember, the Global Planner is in the Primary Cluster’s Optimiser.

Below, the diagram depicts the path of a query in VantageCloud Lake.

Finally, we describe a query’s steps to move through VantageCloud Lake and when it is on every cluster.

Step 1 – First, the user connects to the Session Manager and submits a query. The Session Manager routes the query to the Primary Cluster.

Step 2 – The Primary Cluster’s Parsing Engine parses and optimises the query.

Step 3 – Any portion of the query that uses BFS runs.

• If the query contains no BFS table, it proceeds to step 4.
• If the Compute Cluster is unavailable or not defined, the OFS portion of the query will run from the Primary Cluster.

Step 4 – The Spool passes from the Primary Cluster to the Compute Cluster if it is available to run its part of the query.

Step 5 – The portion of the query with OFS tables work completes.

• If the query contains no OFS table, Lake returns the query results to the user.

Step 6 – Finally, the Compute Cluster passes the last Spool file back to the Primary Cluster to wrap up. Thus, Lake sends the result to the user.

Knowing More about Query Execution in VantageCloud Lake

The excellent Orange Book Life of a Teradata VantageCloud Lake Query discusses how queries run in Lake. Remember that Teradata only makes orange books available to customers.

If it helps, you have a summary of the critical VantageCloud Lake elements and the basis for using them in the post VantageCloud Lake in a Nutshell (it includes an infographic).

I updated this post with the link to the post VantageCloud Lake in a Nutshell on 10 December 2023.

On 29 July 2024, I added the link to the post Compute Clusters in VantageCloud Lake.