Basic features

Fragmentation – spread data across servers by type, for example customer data on one server, items data on another.

Segmentation – spread data across servers by chunks.

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 Replication

DRBD

• filesystem block replication

streaming

• doesn’t work in PostgreSQL with different versions

sync replication

• slower
• consistency

async replication

• faster
• some data loss during failover

cascading replication

• slave download from slave and futher

logical replication

• allow replicate some DB and tables between different servers