David Hao Email & Phone Number

Burlington, Ma

- Providing SQL BI/data warehouse consulting service to multiple clients for their marketing campaign solutions.• Design from scratches, maintain, and add new features to existing DW/BI systems for multiple clients. Communicate with clients collecting new requirements, translate into technical design, document data modeling and dictionary, and build relational diagram. Coordinate with team members in agile project development to identify daily development obstacles, and define the short term work load.• Write complex store procedures and functions, work on performance tunings, review index usage, and work on large table partitioning (sliding windows scenarios). Stay tuned in new database technologies.• Create SSIS to load multiple source data (flat, xml, excel files) to staging tables, and process them into data warehouse. Worked on loading decrypted data between different database platforms (SQL Server and Netezza) in a secure channel. Provide transparent data layer to data analyst. Created ETL monitoring tools to identify deadlock queries, long running queries, erroneous data rows, as well as guarantee data flow in a quick and accurate way.

Leading a team maintaining and upgrading the company’s real-time data warehouse system by providing clean, accurate, and up-to-date data to main product of APM portal. Maintain ETL framework to guarantee data warehouse in a low-latency from operational data system. Researched into the existing design to identify the ETL bottle neck and provide solution options. One milestone is to reduce the data loading cycle from 15 minutes to 8 minutes (mean DW only 8 minutes latent from ODS, in a 10 TB data scale environment).Research into the existing design and document the data warehouse data modelling and data dictionary. Identify and document ETL data flow from source transactional warehouse to staging server to BI warehouse, which is used as instruction document for new developers.Understand new business requests and translate them into data warehouse design specifications using Kimball methodology. Develop functional design document and review with developers and business analysts to figure out project schedule and deadline. Organize scrum project meetings within development team to check up project status, identify bottleneck, and make/adjust plan for next iteration. Communicate with project sponsor to demonstrate data structure in plain language, notify current project progress, and discuss new requests. Create, assign, and maintain Jira system to keep track of raised issues, data warehouse bugs, and customer feedbacks. Maintain project planning, functional design, feature implementation, diagrams and charts documents in our online sharing system (Confluence).