Mastering the STAR Method for Powerful Interview Responses (Part 5): Optimizing Data Warehouse Costs

Introduction:

In our ongoing exploration of the STAR method, let's delve into a scenario focused on cost optimization. This scenario is inspired by the blog post "Streamlining Your Data Warehouse: A 75% Cost Reduction Strategy."

Applying the STAR Method (Sample Interview Question):

Question: Describe a situation where you identified and addressed inefficiencies within a system, resulting in cost savings.

STAR Response (Example based on Blog Post):

• Situation: "I was tasked with optimizing the compute costs associated with our data warehouse. The ever-growing volume of data was leading to significant expenses."

• Task: "My challenge was to identify and eliminate unused resources within the data warehouse, ensuring critical workflows relying on this data remained uninterrupted."

• Action: "To pinpoint these hidden cost drivers, I implemented a two-pronged approach. First, I analyzed access logs for dashboards associated with various data sources. By comparing access patterns with expected usage, I identified potentially unused dashboards that could be deprecated. Additionally, I investigated the purpose of data sources without dashboards, differentiating between 'end-state' tables used for analysis and 'intermediate' tables used for processing. Dependency tracing helped identify if intermediate tables were still crucial for downstream workflows feeding active end-state tables."

• Result: "Once we identified potential candidates for removal, we employed a safe and controlled approach. Data pipelines feeding these resources were temporarily paused. We then closely monitored the environment for a predetermined period to ensure no disruptions occurred. If no issues arose, we proceeded with deprecating the resource, either by permanently removing the pipeline code or archiving the data (especially for logging purposes). This meticulous approach resulted in a remarkable 75% reduction in data warehouse compute costs. This not only saved the company significant financial resources but also streamlined our data infrastructure for improved efficiency and manageability."

Highlighting Your Skills:

This STAR response showcases your:

• Analytical skills: Identifying unused resources within a complex system.

• Problem-solving skills: Developing a systematic approach to data warehouse cost optimization.

• Cost-consciousness: Prioritizing cost reduction while ensuring operational efficiency.

• Technical skills: Understanding data warehouse architecture and data pipelines.

• Attention to detail: Implementing a safe and controlled approach to resource removal.