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Handle Missing Dates in SQL
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Handle Missing Dates in SQL

MediumSQL · PostgreSQL

Problem

Explain how you would fill missing dates with zero counts using a date spine and cross join logic.

Return one row per calendar date in the requested range, including dates with no matching activity. Use the provided tables to produce daily counts with zeros where needed.

Output

  1. One row per date in the full date range
  2. Columns: activity_date, event_count
  3. Include dates with no events, with event_count = 0
  4. Sort by activity_date ascending

Schema

events
ColumnTypeDescription
event_idPKBIGINTUnique event identifier
event_dateDATEDate the event occurred
event_typeVARCHAR(50)Type of event
user_idBIGINTUser associated with the event
Tablesevents
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