DynamoDB: Time frame to avoid stale read

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I am writing to dynamoDB using AWS lambda. I am using AWS Console to read data from dynamoDB. But I have seen instances of stale read with latest not records getting updated when trying to pull records under few mins. What is a safe time interval for data pull which would ensure that latest data is available on read? Would 30 mins be a safe interval?

The below is from AWS site: Just want to understand how recent is recent here. "When you read data from a DynamoDB table, the response might not reflect the results of a recently completed write operation. The response might include some stale data"

Regards, Dbeings

amazon-dynamodb
1 Answers

If you must have a strongly consistent read, you can specify that in your read statement. That way the client will always read from the leader storage node for that partition.

In order for DynamoDB to acknowledge a write, the write must be durable on the leader storage node for that partition and one other storage node for the partition.

If you do an eventually consistent read (which is the default), you might get that read you have a 1:3 chance of that read coming from a node that was not part of the write and an even lesser chance that the item has not been updated on that third storage node.

So, if you need a strongly consistent read, ask for one and you'll get the newest of that item. There is no real performance degradation for doing a strongly consistent read.

user_34161350
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