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SQL for Sustained Price Growth
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SQL for Sustained Price Growth

HardSQL · PostgreSQL

Problem

Write a SQL query to identify neighborhoods where home prices have increased by more than 10% year-over-year for three consecutive quarters at Redfin.

Use the quarterly neighborhood price data provided. Treat a quarter as qualifying only when its median sale price exceeds the price from the same neighborhood and quarter in the prior year.

Output

  1. One row per qualifying neighborhood streak of at least three consecutive quarters.
  2. Columns: neighborhood_name, streak_start_quarter, streak_end_quarter, and qualifying_quarters.
  3. Return the full streak boundaries and sort by neighborhood_name, then streak_start_quarter.

Schema

neighborhood_quarterly_prices
ColumnTypeDescription
neighborhood_price_idPKINTUnique quarterly price record identifier
neighborhood_nameVARCHAR(100)Redfin neighborhood name
quarter_startDATEFirst day of the reported quarter
median_sale_priceNUMERIC(12,2)Median home sale price for the neighborhood and quarter
Tablesneighborhood_quarterly_prices
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