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SQL Bottleneck Identification
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SQL Bottleneck Identification

HardSQL · PostgreSQL

Problem

How would you use SQL to identify the top bottlenecks in a supply chain process from transactional data at Ab Inbev Gcc India?

Use the supplied shipment, event, and process-stage data. Treat completed events for non-cancelled shipments as the analysis population, require at least two events per stage, and identify bottlenecks by average excess duration.

Output

  1. Return the top three stages, one row per stage.
  2. Include stage_code, stage_name, event_count, expected_hours, avg_duration_hours, avg_delay_hours, delayed_pct, and bottleneck_rank.
  3. Order by bottleneck rank, with average delay and stage code providing deterministic tie-breaking.

Schema

shipments
ColumnTypeDescription
shipment_idPKINTUnique shipment identifier
origin_facilityVARCHAR(50)Origin facility code
destination_facilityVARCHAR(50)Destination facility code
shipped_atTIMESTAMPShipment dispatch timestamp
statusVARCHAR(20)Current shipment status
process_stages
ColumnTypeDescription
stage_codePKVARCHAR(20)Unique process-stage code
stage_nameVARCHAR(50)Process-stage name
expected_hoursDECIMAL(8,2)Target completion time in hours
shipment_events
ColumnTypeDescription
event_idPKINTUnique process event identifier
shipment_idINTShipment associated with the event
stage_codeVARCHAR(20)Process stage associated with the event
started_atTIMESTAMPStage start timestamp
completed_atTIMESTAMPStage completion timestamp
Tablesshipment_eventsshipmentsprocess_stages
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