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Running Totals for Equipment Events
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Running Totals for Equipment Events

MediumSQL · PostgreSQL

Problem

Given a table of equipment events, how would you calculate running totals by site and date for Swinerton?

Use equipment_events. Treat NULL event_value values as zero, and exclude rows missing site_name or event_date.

Output

  1. One row per site and event date.
  2. Columns: site_name, event_date, daily_event_total, and running_total.
  3. Order by site_name, then event_date ascending.

Schema

equipment_events
ColumnTypeDescription
event_idPKINTUnique equipment event identifier
site_nameVARCHAR(100)Swinerton construction site associated with the event
event_dateDATECalendar date on which the event occurred
event_typeVARCHAR(50)Category of equipment event
event_valueNUMERIC(12,2)Numeric value contributed by the event
Tablesequipment_events
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