Does the IN PartiQL operator query or scan DynamoDB tables?

Question

We need to query a large (2TB+) DynamoDB table to get multiple items based on their partition keys.

We are planning to use PartiQL as it supports the IN operator as such:

SELECT * FROM table_test where pk IN ('1234','1112');

Would this query do DynamoDB query operations or DynamoDB scan operations under the hood?

We would like to avoid table scans due to them being more expensive.

Not a direct answer, but still good to know: you can block PartiQL statements that result in a scan at the IAM level ([source](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ql-iam.html)). It's a good safeguard against regressions. — MikaelF, Aug 19 '22 at 01:46

score 3 · Accepted Answer · answered May 07 '22 at 14:08

Would this query do DynamoDB query operations or DynamoDB scan operations under the hood?

It will be doing multiple DynamoDB queries as your WHERE clause condition statement is filtering on a DynamoDB partition key.

This is confirmed as per documentation:

To ensure that a SELECT statement does not result in a full table scan, the WHERE clause condition must specify a partition key. Use the equality or IN operator.

Does the IN PartiQL operator query or scan DynamoDB tables?

1 Answers1