day-15.sql

-- SQL Advent Calendar - Day 15
-- Title: The Grinch's Mischief Tracker
-- Difficulty: hard
--
-- Question:
-- The Grinch is tracking his daily mischief scores to see how his behavior changes over time. Can you find how many points his score increased or decreased each day compared to the previous day?
--
-- The Grinch is tracking his daily mischief scores to see how his behavior changes over time. Can you find how many points his score increased or decreased each day compared to the previous day?
--

-- Table Schema:
-- Table: grinch_mischief_log
--   log_date: DATE
--   mischief_score: INTEGER
--

-- My Solution:

select log_date, mischief_score,
mischief_score-lag(mischief_score) over(order by log_date) as score_change
from grinch_mischief_log
order by log_date;