Tag archive

#lag

Commands grouped around the same concept, pattern, or recurring problem.

4 commands with this tag Browse related patterns quickly

advanced windowing MySQL MariaDB SQL Server PostgreSQL SQLite

Access Previous And Next Rows With LAG And LEAD

Reference values from preceding or following rows within an ordered partition without writing a self-join.

advanced windowing MySQL MariaDB SQL Server PostgreSQL SQLite

Assign Session IDs Based on Inactivity Gaps

Group a stream of user events into sessions by labelling each event with a session ID that increments whenever the gap since the previous event exceeds a threshold.

advanced windowing MySQL MariaDB SQL Server PostgreSQL SQLite

Compare a Metric Year-Over-Year Using LAG

Pull the prior year's value into the current row with `LAG`, then compute the percentage change — a common pattern for revenue, signups, and other business KPIs.

intermediate windowing MySQL MariaDB SQL Server PostgreSQL SQLite

Name a Window Definition for Reuse

Define a window specification once with a `WINDOW` alias and reference it in multiple `OVER` clauses — avoiding repetition when several window functions share the same partition and ordering.