Gartner Peer Insights receives review records from periodic ingestion jobs, and the same review can appear multiple times as it is updated. Write a PostgreSQL query that returns one latest valid record for each (source_system, source_review_id) key.
source_review_id or source_updated_at.ROW_NUMBER() to rank records by the most recent source_updated_at within each key.ingestion_id descending as a deterministic tie-breaker when timestamps match.source_system, then source_review_id.| Column | Type | Description |
|---|---|---|
| ingestion_idPK | INT | Unique ingestion record identifier |
| source_system | VARCHAR(40) | Originating Gartner review surface |
| source_review_id | VARCHAR(30) | Review identifier from the source system |
| source_updated_at | TIMESTAMP | Last update time reported by the source |
| status | VARCHAR(20) | Review lifecycle status |
| rating | INT | Review rating from 0 to 5 |
| review_title | VARCHAR(120) | Review title |