Massive multi node postgreSQL/BDR in Retail System

speaker: Julyanto Sutandang, Equnix Business Solutions event: FOSSASIA 2017

Requirements for POS

• data collection from 3.4K POS terminals to head office
• distribute new items to stores
• distribute price updates to stores
• POS can serve when network is down

Design of the system

• POS can use flat files as it is sequential.
• Sync from POS to store database
• Sync from store database to head office database with BDR

Bi-directional replications, supporting multi master

• store adds records from POS
• head office adds items, update prices
• 200 cluster, each cluster has one node in the store and one node in the head office

Realtime monitoring of replication status of each cluster, versioning of items

• easier to monitor as BDR provides the stats

Not all objects are replicated

• sequences
• non database objects, eg role