KKkyuwon kanginq1.hashnode.dev·May 4, 2025 · 2 min read[PostgreSQL] COALESCEWHAT IS COALESCE()? In simple terms, COALESCE() helps you choose the first non-null alue from a list. BASIC SYNTAX COALESCE(value1, value2, value3, ...) It checks each value in order and returns the first one that is not NULL. SIMPLE EXAMPLES -- exa...00
KKkyuwon kanginq1.hashnode.dev·May 4, 2025 · 3 min read#3 Creating integrated client table + Basic AnalysisOnce I had cleaned the raw files (visit_history_clean, client_info_raw, and invoice_raw), my next goal was to combine them into a single, master-level view of every customer—no matter which dataset they appreaed in. Each dataset offered part of the p...00
KKkyuwon kanginq1.hashnode.dev·Apr 21, 2025 · 2 min read#2 Cleaning Raw Data for BI AnalysisAfter importing the raw CSV files into PostgreSQL, the first thing I tacked was cleaning and standardizing the datasets to make them analysis-ready. What kind of cleaning? It started with the basics: Fixing blank or inconsistent values Converting d...00
KKkyuwon kanginq1.hashnode.dev·Apr 19, 2025 · 2 min read[PostgreSQL] ALTER TABLEAfter importing the raw CSV files into PostgreSQL, I noted that many of the columns were set to generic data types like varchar(50) or even just text. Totally normal, but definitely not ideal if you’re planning to run serious analysis. What does ALTE...00
KKkyuwon kanginq1.hashnode.dev·Apr 19, 2025 · 2 min read#1 My First BI Project - Project OverviewThis is my very first Business Intelligence analysis project after pivoting from a 7-year career in eCommerce strategy to business intelligence. I wanted to get closer to the data, explore customer behavior on a deeper level, and build an analytical ...00
