Median Age - SQL Interview Query 20 | SQL Problem Level "MEDIUM"

A walkthrough of solving a SQL interview problem to find the median age per country. The solution uses PostgreSQL window functions (ROW_NUMBER with PARTITION BY country ORDER BY age) to rank rows within each country group, then applies a mathematical formula using integer division and casting to decimal to correctly identify middle rows for both even and odd record counts. The approach handles edge cases like single-record countries and uses a frame clause (RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) to get accurate total counts per partition.