Database Reference
In-Depth Information
represent arbitrary area features, which means each Geohash-index record stored in Dy-
namoDB. But we can store this information if it's a small geographical area, otherwise the
spatial feature is stored as an object in S3, with a pointer to the S3 location that is stored
in DynamoDB.
DynamoDB is presently provisioned completely on SSD devices. SSD devices can read
requests in a small fraction of time as compared to a magnetic disk (about 100 times
faster) by servicing individual data, though the cost per GB of storage is much higher (ap-
proximately 10 times) than that of a magnetic disk. Hence DynamoDB can provide very
low latency and high throughput compared to S3 but at a higher cost per unit of storage.
Let's take a scenario in which 1 GB of DynamoDB storage costs $1 per month, while S3
storage costs between 4 cents and 12 cents per GB per month. This means it is eight times
cheaper than DynamoDB. DynamoDB also provides a flexible fee structure based on the
IO capacity. In this, 1,000 read operation per second will cost around 20 cents per hour,
and the write operation is about 5 times more expensive, because SSDs can perform a
read operation much faster than a write operation.
Now take a look at the tabular comparison between DynamoDB and S3:
Specification
DynamoDB
S3
Data model
Key-value store
Store object/data in bucket
Operating system
Cross platform (hosted) Cross platform (hosted)
License
Commercial (Amazon) Commercial(Amazon)
Data storage
Solid-state drive (SSD) Magnetic disk
Secondary indexes
Yes
No
Accessing method
API call
HTTP web address (API + publicly accessible URL)
Server-side script
No
No
Composite key support
Yes
No
Data consistency
Yes
Yes
