- Round robin
- Hashing
- Replication
Round robin: Data is spread evenly among all the 60 underlying distributions without any regard to data values. There is no specific key used to distribute data.
Hashing: Most common and effective data distribution method. Data is distributed according to the most common distributed according to the value of a selected column.
![Distributed table Distributed table](https://docs.microsoft.com/en-nz/azure/sql-data-warehouse/media/sql-data-warehouse-distributed-data/hash-distributed-table.png)
Replication: Data is copied to every database rather than being split up. Replication is good small lookup tables or dimension tables that are frequently joined with other big tables.
![Replicated table Replicated table](https://docs.microsoft.com/en-nz/azure/sql-data-warehouse/media/guidance-for-using-replicated-tables/replicated-table.png)
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