October 25, 2026
Choose Offset or Keyset Pagination with Evidence
Offset paging is convenient; keyset paging can keep deep sequential pages efficient and stable.
TOPIC
SQL
Relational query design and SQL interview practice.
October 25, 2026
Make PostgreSQL Upserts Safe and Idempotent
Use a unique key, ON CONFLICT, and a transaction boundary that matches the business operation.
October 25, 2026
Use SQL Window Functions for Rankings and Trends
Rank rows within groups and calculate running metrics without collapsing detail rows.