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The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

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Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#101

Post by nuclearnice1 »

glkz wrote: post #81
dropofwill wrote: post #66

Earlier quoted context omitted.

Note that Cassandra has similar limitations with data/throughput, but they aren't enforced or documented (because they depend on your particular setup) and your queries just fail or worse make all queries to the same node in the cluster fail (fun times with large wide rows). The rich data types in Dynamo are quite strange, since they're basically useless for querying I'm not sure why you would use them. Maybe I'm mis…

The rich data types are also useful for partial updates, like adding items to a set, updating some fields in a map etc.

That does sound useful.

So I can have a key and an associated map and update a few members of the map?

I would like to learn how to do that.

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#102

Post by sudhirj »

abd12 wrote: post #37
arpinum wrote: post #24

I bought the book, I read the book, I've used DynamoDB for awhile. It didn't change my mind. DynamoDB makes tradeoffs in order to run at massive scale, but scale isn't a problem many people need solving when 2TB of RAM fits in a single box. Meanwhile I need to handle eventual consistency, an analytics pipeline, another database for fuzzy search, another geo lookup database, Lambda functions to do aggregations, and a…

Fair enough! I think that's a reasonable position. IMO, there are two times you should absolutely default to DynamoDB: - Very high scale workloads, due to its scaling characteristics - Workloads w/ serverless compute (aka Lambda) due to how well it fits with the connection model, provisioning model, etc. You can use DynamoDB for almost all OLTP workloads, but outside of those two categories, I won't fault you for cho…

Not to mention the same also applies for load. You get about 10ms at 10, 1000 or 1000000 requests per second, again irrespective of how much data you have.

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#103

Post by taylor-s »

nuclearnice1 wrote: post #101
glkz wrote: post #81

Earlier quoted context omitted.

The rich data types are also useful for partial updates, like adding items to a set, updating some fields in a map etc.

That does sound useful. So I can have a key and an associated map and update a few members of the map? I would like to learn how to do that.

Yep! Here's the AWS documentation about this feature: https://docs.aws.amazon.com/amazondynamodb/latest/developerg....

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#104

Post by Ambol »

arpinum wrote: post #24

I bought the book, I read the book, I've used DynamoDB for awhile. It didn't change my mind. DynamoDB makes tradeoffs in order to run at massive scale, but scale isn't a problem many people need solving when 2TB of RAM fits in a single box. Meanwhile I need to handle eventual consistency, an analytics pipeline, another database for fuzzy search, another geo lookup database, Lambda functions to do aggregations, and a…

>but scale isn't a problem many people need solving when 2TB of RAM fits in a single box.

What's the price of that on the cloud? I know I can run crazy big tables on DynamoDB for a couple of dollars. I don't know what 1 month of a relational database with 2TB of RAM costs on the cloud, but I am pretty sure I can't afford it.

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#105

Post by arpinum »

ryanmarsh wrote: post #93
arpinum wrote: post #24

I bought the book, I read the book, I've used DynamoDB for awhile. It didn't change my mind. DynamoDB makes tradeoffs in order to run at massive scale, but scale isn't a problem many people need solving when 2TB of RAM fits in a single box. Meanwhile I need to handle eventual consistency, an analytics pipeline, another database for fuzzy search, another geo lookup database, Lambda functions to do aggregations, and a…

Very disappointed to find the top comment is about DynamoDB and not Alex and his wonderful book. I suppose this is par for the course with HN. I hope nothing I create ever ends up posted here.

You are disappointed the comment is about the subject of the book from someone who read it and didn’t find it a compelling read? I didn’t like the book because it continued a trend in mia-selling DynamoDB and my comment reflects that frustration. Sorry but not every review is going to be glowing, and I’m certainly not going to make personal comments about the author.

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#106

Post by sudhirj »

avip wrote: post #42
DVassallo wrote: post #32

Earlier quoted context omitted.

If you treat DynamoDB as a DBMS, you’re going to be disappointed (for the reasons you mention). But if you think of it as a highly-durable immediately-consistent btree in the cloud, it’s amazing. DynamoDB is closer to Redis than MySQL. Amazon does it a disservice by putting it in the databases category.

DynamoDb is like redis without the fun data structures, the fantastic cli and discoverability, the usefull configurable tradeoff between fast and consistent, and really much-needed features s.a listing your keys.

So my quarantine project is building a Redis API on top of DynamoDB - https://github.com/sudhirj/redimo.go

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#107

Post by abd12 »

dkobia wrote: post #94
abd12 wrote: post #3

Waves Author here. Happy to answer any questions folks have about the book, about DynamoDB, or about self-publishing. NoSQL modeling is waaay different than relational modeling. I think a lot of NoSQL advice out there is pretty bad, which results in people dismissing the technology altogether. I've been working with DynamoDB for a few years now, and there's no way I'll go back. The book has been available for about a…

Any chance for a Kindle friendly mobi?

Yep! It comes with PDF, MOBI, and EPUB formats :)

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#108

Post by Aeolun »

outworlder wrote: post #87
philipkglass wrote: post #52

Earlier quoted context omitted.

Others are comparing DynamoDB to Redis and Cassandra. It has additional limitations. These are fairly clearly spelled out but maybe weren't highlighted as prominently a few years back. (I say that because I inherited an application that made heavy use of DynamoDB but turned out not to be a great fit for DDB.) - It provides rich types with some odd limitations: strings, sets, lists, and binaries do not allow empty val…

> - It provides rich types with some odd limitations: strings, sets, lists, and binaries do not allow empty values. That is _infuriating_ It's documented, but it is so surprising when you first hit it. Sometimes, empty values have semantics attached to them, I don't want to scrub them out.

I think that basically describes DDB in a nutshell. You think it’s like Mongo, only on AWS, but then you slowly find out it’s much, much worse (for most use cases that you’d go with Mongo).

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#109

Post by Aeolun »

mmbleh wrote: post #64
abd12 wrote: post #58

Earlier quoted context omitted.

True! I'm not a huge fan of Aurora Serverless and the Data API. The scaling for Aurora Serverless is slow enough that it's not really serverless, IMO. And the Data API adds a good bit of latency and has a non-standard request & response format, so it's hard to use with existing libraries. But it's definitely an option for those that want Lambda + RDBMS. The RDS Proxy is _hopefully_ a better option in this regard but…

Differing opinion - I think RDS Proxy is the wrong approach. Adding an additional fixed cost service to enable lambda seems like an indicator of a bad architecture. In this case the better approach would likely be to just use a Fargate container which would have a similar cost and fewer moving parts. By the time you pay a fixed cost for the proxy on top of what you already pay for the RDS server, it'd be a far simple…

> By the time you pay a fixed cost for the proxy on top of what you already pay for the RDS server, it'd be a far simpler architecture with less moving parts to just run a Fargate container

A lot of people want to use lambda (or serverless) even so. So AWS is just accommodating their wishes.

Re: The DynamoDB Book: Data Modeling with NoSQL and DynamoDB

#110

Post by raynguyen »

This looks like a great resource. One thing I'm struggling with is the ability to sort and filter and was wondering if the book goes into detail about this topic.

If I have a person entity and its attributes listed out in a table. How would you go about sorting by first name, last name, created at, etc... I was thinking of streaming everything over to elastic search, but that would add extra complexity to maintain.

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