Two-Week SQL Learning Recap Covers Window Functions, Joins, CTEs and Subqueries

A developer documents two weeks of intensive SQL study at luxdevHQ, starting from the basics. The write-up walks through window functions such as ROW_NUMBER, RANK, LAG and LEAD, along with aggregate functions like COUNT, SUM, MAX and MIN. It also covers the join types (inner, left, right, full outer, cross and self) and explains Common Table Expressions alongside several subquery forms. Each concept is illustrated with example queries drawn from a hospital visits dataset.