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  5. Best Practices of Table Design
  6. Using Partitioned Tables

Using Partitioned Tables

Partitioning refers to splitting what is logically one large table into smaller physical pieces based on specific schemes. The table based on the logic is called a partitioned table, and a physical piece is called a partition. Data is stored on these smaller physical pieces, namely, partitions, instead of the larger logical partitioned table. A partitioned table has the following advantages over an ordinary table:

  1. High query performance: The system queries only the concerned partitions rather than the whole table, so the query efficiency is improved.
  2. High availability: If a partition in a partitioned table is faulty, data in the other partitions is still available.
  3. Easy maintenance: To fix a partitioned table having a faulty partition, you simply need to fix the partition.

DWS supports range partitioned tables.

Range-partitioned table: Data within a specific range is mapped onto each partition. The range is determined by the partition key specified during the partitioned table creation. The partition key is usually a date. For example, sales data is partitioned by month.