Best Practices for Handling Time Series Data in DynamoDB - Amazon DynamoDB

Best Practices for Handling Time Series Data in DynamoDB

General design principles in Amazon DynamoDB recommend that you keep the number of tables you use to a minimum. For most applications, a single table is all you need. However, for time series data, you can often best handle it by using one table per application per period.

Design Pattern for Time Series Data

Consider a typical time series scenario, where you want to track a high volume of events. Your write access pattern is that all the events being recorded have today's date. Your read access pattern might be to read today's events most frequently, yesterday's events much less frequently, and then older events very little at all. One way to handle this is by building the current date and time into the primary key.

The following design pattern often handles this kind of scenario effectively:

  • Create one table per period, provisioned with the required read and write capacity and the required indexes.

  • Before the end of each period, prebuild the table for the next period. Just as the current period ends, direct event traffic to the new table. You can assign names to these tables that specify the periods they have recorded.

  • As soon as a table is no longer being written to, reduce its provisioned write capacity to a lower value (for example, 1 WCU), and provision whatever read capacity is appropriate. Reduce the provisioned read capacity of earlier tables as they age. You might choose to archive or delete the tables whose contents are rarely or never needed.

The idea is to allocate the required resources for the current period that will experience the highest volume of traffic and scale down provisioning for older tables that are not used actively, therefore saving costs. Depending on your business needs, you might consider write sharding to distribute traffic evenly to the logical partition key. For more information, see Using Write Sharding to Distribute Workloads Evenly.

Time Series Table Examples

The following is a time series data example in which the current table is provisioned at a higher read/write capacity and the older tables are scaled down because they are accessed infrequently.

        Table schema for high-volume time-series data.