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Find Vehicles With Error Code Bursts
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Find Vehicles With Error Code Bursts

MediumSQL · PostgreSQL

Problem

How would you use a SQL join and conditional aggregation to identify connected vehicles that have experienced more than three distinct error codes in a single shift at Bosch?

Use the vehicles, vehicle_shifts, and vehicle_error_events tables. Return only qualifying connected vehicle shifts.

Output

  1. One row per qualifying vehicle and shift
  2. Columns: vehicle_id, shift_id, shift_date, and distinct_error_codes
  3. Sort by vehicle_id, then shift_id ascending

Schema

vehicles
ColumnTypeDescription
vehicle_idPKINTUnique vehicle identifier
vehicle_modelVARCHAR(80)Vehicle model name
is_connectedBOOLEANWhether the vehicle is connected to Bosch vehicle services
vehicle_shifts
ColumnTypeDescription
shift_idPKINTUnique shift identifier
vehicle_idINTVehicle assigned to the shift
shift_dateDATECalendar date of the shift
shift_nameVARCHAR(20)Shift label
vehicle_error_events
ColumnTypeDescription
event_idPKINTUnique error event identifier
shift_idINTShift during which the event occurred
error_codeVARCHAR(20)Reported diagnostic error code
event_timestampTIMESTAMPTime when the error was recorded
Tablesvehiclesvehicle_shiftsvehicle_error_events
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