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Issue: PicardAggregator ETL fails with (COGNOS.SLXRE2_PAGG_SAMPLE_PK) violated error.

Cause: 

1. Most likely Is_latest flag is set for more than 1 aggregations.
2. Another case is when samples are reprocessed on the cloud, sample renaming and research project renaming, where the old aggregation needs to be set to "not latest".

Remedy: 

1. There is an agent that looks for certain Is_latest flag violations (IsLatestCop) that specifies the list of metrics.aggregation records with the issues and automatically opens a PO ticket in the pipeline.
2. Find the sample that causes it (run the query below) and make a blocker PO ticket + notify somebody from Pipeline team to address it ASAP because the ETL won't recover until this is fixed.