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Rolling 7-Day SQL Window
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Rolling 7-Day SQL Window

MediumSQL · PostgreSQL

Problem

Write a SQL query using window functions to calculate a rolling 7-day average for each product or user.

Use entities and daily_metrics. Include only products and users with metric observations. The rolling period includes the current date and the preceding six calendar days; missing dates do not contribute values.

Output

  1. One row per product or user metric observation
  2. Columns: entity_name, entity_type, metric_date, metric_value, rolling_7_day_avg
  3. Order by entity_type, entity_id, and metric_date ascending

Schema

entities
ColumnTypeDescription
entity_idPKINTUnique identifier for a product or user
entity_typeVARCHAR(20)Entity classification, such as Product or User
entity_nameVARCHAR(100)Display name of the entity
daily_metrics
ColumnTypeDescription
metric_idPKINTUnique identifier for a daily metric observation
entity_idINTReferenced product or user identifier
metric_dateDATEDate of the metric observation
metric_valueDECIMAL(10,2)Metric value recorded for the entity and date
Tablesentitiesdaily_metrics
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