Yawei Zhang / Data & BI · Business process automation
I build Power BI reporting, SQL analyses and internal applications that reduce manual work and make business rules easier to understand and check.
Workplace efficiency figures are retrospective estimates and vary with workload and task complexity.
Selected work
Open a project to inspect architecture, code and validation.
I consolidated recurring procurement and fleet data into Power BI reporting, with latest-month KPIs, supplier and contract analysis, and explicit reconciliation checks.
I developed an Access/VBA quotation workflow with supplier catalogue lookups, cost aggregation, gross-margin pricing and quotation output.
I analysed delivery reliability and customer reviews in PostgreSQL, controlling join grain, validating KPI denominators and comparing query plans.
Working method
My approach
Understand the decision → inspect data quality → define business rules → implement → validate → document trade-offs.
I prioritise correct aggregation grain, reconciled totals, meaningful KPIs and workflows that people can use without unnecessary manual interpretation.
The other half of the story
My Notion portfolio covers the full business-facing case studies, including WIP Workflow & Billing Optimization, which focuses on process redesign, pilot testing and user adoption rather than publishable source code.
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