11 ms·

Azure Cosmos DB, a globally distributed database

336 points by andysinclair 9y ago

judah 9y ago
This isn't a new database. This is a rebranding of the generically-named Azure DocumentDB, plus some new features.
- sealord 9y ago
  Not exactly. DocumentDB was primarily a document store. Cosmos allows you to store graphs and KV pairs as well.
  - jchrisa 9y ago
    I was unable to glean from a quick read of the consistency documentation, does CosmosDB support uniqueness and foreign key constraints?
    - sealord 9y ago
      Afraid not - there's no real concept of constraints with CosmosDB.
  - aliostad 9y ago
    DocumentDB is KV.
    - rattray 9y ago
      DocumentDB looks like a JSON document store?
      - hoschicz 9y ago
        It is.
  - cowardlydragon 9y ago
    um, property graphs are basically document databases with a special "relationships" property. Then you add the graph algorithms. Key-value is a reduction of document storage.
- henriksen 9y ago
  Not really. It's a new database and is a superset of DocumentDB.
  - antonb9 9y ago
    It's also hosted on the Moon, so it's not just globally distributed but planetary distribution as well. If anything happens to Earth, your data will be safe.
    - henriksen 9y ago
      I thought the secondary was located on Mars?
      - antonb9 9y ago
        Elon Musk has already claimed that planet.
  - dharmashuklaMS 9y ago
    Azure Cosmos DB has been many years in the making. Azure Cosmos DB started as “Project Florence” in late 2010 to address developer the pain-points faced by large scale applications inside Microsoft. Observing that the challenges of building globally distributed apps are not a problem unique to Microsoft, in 2015 we made the first generation of this technology available to Azure developers in the form of DocumentDB. Since that time, we’ve been steadily adding new capabilities both in the database engine as well as, larger distributed system components. Azure Cosmos DB is the result. It is the next big leap in globally distributed, at scale, cloud databases. As a part of this release of Azure Cosmos DB, DocumentDB customers, with their data, are automatically Azure Cosmos DB customers. They now have access to the new system and capabilities offered by Azure Cosmos DB today as well as, as we keep evolving the service.
    - curiousDog 9y ago
      Does Cosmos DB support distributed transactions like Spanner? Would be nice to see a deeper dive into Transactions like how isolation works etc.
Dimi9909 9y ago
is this similar to DynamoDB in AWS?
jasondc 9y ago
> Latency: 99.99% of <10 ms latencies at the 99th percentile Impressive SLA to guarantee, I'm curious if this will hold up in all random customer workloads that are coming, e.g. updating a lot of fields in a large document (or just a very large insert).
- bigtones 9y ago
  Agreed - seems like a rebranding in response to Google Cloud Spanner DB announcement a couple of months back. Microsoft's marketing seems to be pushing some of the same outcomes in the ad copy.
- Dimi9909 9y ago
  this is a little bit hard to believe. Inter region Ping can even take longer than 15ms... I guess this SLA is for eventual consistency model not strong consistency model
  - aravindkr1 9y ago
    The latency SLAs are within the same Azure region. You can distribute your data across any of the 30+ regions that Azure is available in. Your apps always read from the local/closest region with the homing APIs.
    - xapata 9y ago
      That didn't answer the question: will all regions be always consistent?
      - GovindMS 9y ago
        We would invite you to explore the consistency levels available in Cosmos DB. As a developer you can choose what makes most sense in distributed scenario. https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb... Eventual is one end of the consistency. But then consistent prefix, session (if you can control) and bounded staleness all can play a role.
chaostheory 9y ago
Is it open source? Why do I care? The same reason I don't use AWS or Google Cloud only datastores: I want to avoid vendor lockin.
- cheeze 9y ago
  > Is it open source? Probably not > Why do I care? You might not. > The same reason I don't use AWS or Google Cloud only datastores: I want to avoid vendor lockin. Sounds like this isn't the product for you then. Is that a surprise?
  - chaostheory 9y ago
    My questions were rhetorical. One reason I post my thoughts here is because companies like MS are on HN. It's useful to know why people don't want to use your product or are hesitant to do so. Besides, MS has been doing a lot of surprising things lately post-Ballmer.
    - obmelvin 9y ago
      This is meant for people who need services and guarantees that can only be provided by a huge infrastructure provider
      - chaostheory 9y ago
        You can say the same for pretty much every other managed datastore service
- oedenfield 9y ago
  See the news about Azure Database for MySQL and Postgresql https://azure.microsoft.com/en-us/services/postgresql/ https://azure.microsoft.com/en-us/services/postgresql/ https://azure.microsoft.com/en-us/services/mysql https://azure.microsoft.com/en-us/services/mysql
- Thaxll 9y ago
  Vendor lock in is a bad example, it's not like you're going to move your infrastructure from AWS to Google every 6months. And if you do you will have many more complicated problems than vendor lock in.
martinknafve 9y ago
No backup/restore?
- bpicolo 9y ago
  They guarantee durability. I imagine that's a part of it? I guess no backup/restore is a problem if you manage to delete all your data, so we'd have to see some docs, heh
  - martinknafve 9y ago
    At some point someone will accidentally overwrite or delete data and discover that some days later...
- oedenfield 9y ago
  Backup is automatic and restore is available within a time frame. https://docs.microsoft.com/en-us/azure/documentdb/documentdb-online-backup-and-restore https://docs.microsoft.com/en-us/azure/documentdb/documentdb...
  - martinknafve 9y ago
    > If the data is accidently dropped or corrupted, please contact Azure support within 8 hours Thats sounds less then optimal. :)
    - dharmashuklaMS 9y ago
      For supporting the "oops I accidentally deleted my table/collection/graph - how do I get it back?" scenario, Cosmos DB automatically takes periodic, full backups of all your data. Currently, we restore your backups on demand and its free - you just send a mail to us. In a few months, we will expose an API using which you can restore the data you accidentally deleted yourself.
- dharmashuklaMS 9y ago
  Cosmos DB does local persistence and replication both within a region and across any number of regions.All data is durable and made highly available via replication. You dont need to take backups or restore them for ensuring durability or availability. See (1) https://docs.microsoft.com/en-us/azure/cosmos-db/introduction https://docs.microsoft.com/en-us/azure/cosmos-db/introductio... and (2) https://docs.microsoft.com/en-us/azure/cosmos-db/introduction#global-distribution https://docs.microsoft.com/en-us/azure/cosmos-db/introductio.... That said, if you need backup/restore for the cases where you accidentally delete your data and want to resurrect it, Cosmos DB automatically takes backups for you periodically.
anand_MSFT 9y ago
See https://www.youtube.com/watch?v=Yfmw7swCtZs https://www.youtube.com/watch?v=Yfmw7swCtZs by Turing Award Winner, Dr. Leslie Lamport, as he talks about Azure Cosmos DB
dmarlow 9y ago
I want a competitor to Google Cloud SQL in Azure.
- curiousDog 9y ago
  It's called Azure SQL DB (unless you want Mysql, then you'd want IaaS SQL DB)
  - dmarlow 9y ago
    With the exception that Azure SQL doesn't horizontally scale across regions/datacenters like Google Cloud SQL does.
    - curiousDog 9y ago
      I don't think Google Cloud SQL does either in a fully managed way. Spanner OTOH does that but it's NewSQL. Traditional sharding has been supported for a while: https://docs.microsoft.com/en-us/azure/sql-database/sql-database-elastic-scale-introduction https://docs.microsoft.com/en-us/azure/sql-database/sql-data.... you can create databases where ever you want.
henriksen 9y ago
Talk about the foundations of Cosmos DB: https://www.youtube.com/watch?v=Yfmw7swCtZs https://www.youtube.com/watch?v=Yfmw7swCtZs
VikingCoder 9y ago
I'd like to see an in-depth comparison with Google Cloud Spanner.
- 0xFFC 9y ago
  Exactly, although cloud is not my best suite, I am so exited. This is serious fight.
- afeezaziz 9y ago
  Is there a real life case study of people/startup using Cloud Spanner? I am wondering what are the use cases of Spanner that cannot be fulfilled by other Google Cloud Platform products.
  - random3 9y ago
    relational model globally distributed ACID transactions 99.999 availability to name a few
    - arosenbaum 9y ago
      Please post link where they talk about transactions - I can't find it in the docs anywhere. Availability SLA is clearly not 5 9's - https://azure.microsoft.com/en-us/support/legal/sla/cosmos-db/v1_0/ https://azure.microsoft.com/en-us/support/legal/sla/cosmos-d...
      - nindalf 9y ago
        random3 is replying to someone asking about Google's Spanner, which does have those transactions.
- daxfohl 9y ago
  They're very different things. It's like wanting an in-depth comparison between SQL Server and Redis.
dharmashuklaMS 9y ago
Hi, This is Dharma from Azure Cosmos DB team. We are super excited to make the service available today.We published the first of the series of technical blog posts here -> https://azure.microsoft.com/en-us/blog/a-technical-overview-of-azure-cosmos-db/ https://azure.microsoft.com/en-us/blog/a-technical-overview-.... Would love to answer any Cosmos DB questions.
- tosh 9y ago
  Can you give an overview on how Cosmos differs from Spanner and CockroachDB?
  - dharmashuklaMS 9y ago
    There are many significant differences in capabilities, and design approaches between other systems and Cosmos DB. At a very high level. differences are at two levels - the design of the database engine and the larger distributed system. The database engine design is inspired on LLAMA http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-levandoski.pdf http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-..., Bwtree - > https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19dd54bb6c773736a.pdf https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d... and schema-agnostic indexing techniques -> http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf. Please note that these papers are significantly behind the current state of the implementation. The most crucial aspect that these papers dont cover is the integration of the database engine with the larger distributed system components of Cosmos DB including the resource governance, partition management, and the implementation of replication protocol /consistency models etc. Our goal is to publish all of the design specifications including TLA+ specs over time.
- daxfohl 9y ago
  Are graph ops/queries atomic? i.e. if you run a tree query on a tree-graph, at the same time you're re-parenting a treenode, is there a chance that the node could end up in the result tree twice or zero times? Also, if they're atomic, are they optimistic or pessimistic transactions? Also if they're atomic, does that mean queries done on the write server? (My understanding is that readonly transactions on read-replicas are not supported, or at least they weren't under DocDB). Any lay-programmer insight into what's going on under the hood, or at least performance/atomicity implications, without giving up too much proprietary info, would be appreciated.
willchen 9y ago
Very interesting DB service. If I'm reading the docs right it sounds like you can't do JOINs across documents? https://docs.microsoft.com/en-us/azure/documentdb/documentdb-sql-query#a-idadvancedaadvanced-database-concepts-and-sql-queries https://docs.microsoft.com/en-us/azure/documentdb/documentdb...
- extesy 9y ago
  Not using DocumentDB API but you can kinda do joins using graph traversal Gremlin API.
rattray 9y ago
I find this product slightly befuddling. It seems like a "just throw all your data in this" kind of database, probably intended for everything but core application relational data (so, good for analytics, messaging, etc). It sounds like the atom-record-sequence model at the heart of it is pretty key, but there's not a lot in the article about what that is and how it works. Is this a well-understood data structure used elsewhere? The project seems very ambitious, and I could see it being used pretty heavily at a lot of companies. Thoughts?
- datasage 9y ago
  Its not uncommon to in sass stacks to have multiple data stores, each specialized for different use cases. I do see it appealing to have one system that can support each type of use case and able to tune that as needed.
joshuatalb 9y ago
This feels like MS' version of Google's Cloud Spanner that's GA in a few days. Same kind of marketing too.
- strmpnk 9y ago
  Having evaluated both, I'd say Cloud Spanner is quite a bit behind in some regards. It's not that Spanner itself can't do something but that Cloud Spanner hasn't productized some important features like multi-datacenter failovers. It's certainly coming but CosmosDB (aka. DocumentDB) does a lot of this today (and has been for awhile as this is not entirely new).
  - azurezyq 9y ago
    But from Cosmos DB's doc, cross-dc strong consistency seems not even supported. https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb... "Azure Cosmos DB accounts that are configured to use strong consistency cannot associate more than one Azure region with their Azure Cosmos DB account."
    - strmpnk 9y ago
      I didn't claim cross-dc consistency. I said failover, which is shockingly hard to make many competitors do. The key here is that only one DC can take writes but the failover works transparently with your client (also with clear SLAs).
      - lern_too_spel 9y ago
        Why do you need failover if you have global multimaster like Spanner?
        aliuy 9y ago
        An interesting thing to point out is the current beta for Cloud Spanner does not have multi-region deployments... and instead, allows you to do single-region deployment in your choice of 3 (not >30) regions: https://cloud.google.com/spanner/docs/instance-configuration https://cloud.google.com/spanner/docs/instance-configuration
ahelwer 9y ago
Designed with TLA+! :D Small interview with Leslie Lamport: https://techcrunch.com/2017/05/10/with-cosmos-db-microsoft-wants-to-build-one-database-to-rule-them-all/ https://techcrunch.com/2017/05/10/with-cosmos-db-microsoft-w... Hope Cosmos team releases a whitepaper on their experiences with the language. I'd heard snatches of gossip here and there that TLA+ was used inside Cosmos, but no concrete details. edit: apparently there's also a video of Lamport talking about this https://www.youtube.com/watch?v=L_PPKyAsR3w https://www.youtube.com/watch?v=L_PPKyAsR3w
- dmix 9y ago
  The effort to formalize the database was apparently led by: > Leslie Lamport the Turing Award winner whose work underpins many of these concepts (and who also wrote the LaTeX document preparation system) and who joined Microsoft Research in 2001 Quote about TLA+: > As Shukla noted, though, his idea here was to build a database system that could last decades. To do this, he also brought in Lamport to teach the team TLA+. Lamport has long had a special interest in how developers spec out their applications. TLA+ is essentially a formal language for doing just that. “When we started out in 2010, we wanted to build a system — a lasting system. This was the database of the future for Microsoft,” Shukla told me. “We try to apply as much rigor to our engineering as we possibly can. […] TLA+ has been wonderful in getting that level of rigor in a team of engineers to set the bar high for quality.” TLA+, Lamport noted, allows you to do the high-level design of a system in a completely formal way — and because it’s done formally, it can be checked for correctness, too (and to be fair, AWS and others also use TLA+ to spec out their distributed systems). “I don’t want to give the impression that TLA+ is great and I’m brilliant. It’s great because it’s almost entirely based on mathematics,” Lamport added.
- OriginalJGC 9y ago
  Here is a longer version with Dr. Lamport with more details https://www.youtube.com/watch?v=L_PPKyAsR3w&feature=youtu.be https://www.youtube.com/watch?v=L_PPKyAsR3w&feature=youtu.be
- Quiark 9y ago
  Wow, that's cool. TLA+ is the same formalism that Amazon uses to verify (some of) their cloud services.
dagi3d 9y ago
If I understood it correctly, they mentioned they offer horizontal scalibility for their databases and I wonder how does it work for the graph data model
- aravindkr1 9y ago
  This is covered in https://docs.microsoft.com/azure/cosmos-db/gremlin-support https://docs.microsoft.com/azure/cosmos-db/gremlin-support. You can specify a partition key for your graphs for scale out, and access vertices and edges using the partition key + item key ("id") like g.V(['USA', 'Seattle']).
tracker1 9y ago
From the intro page[1]... Many of the descriptions comparing to NoSQL are wrong. There are plenty of NoSQL options that have similar features, though it isn't universal, it can and often is there. Cassandra, for example, probably does just as well in multi-zone/dc concurrency. Consistency options are also similarly tunable. Cockroach 1.0 was announced earlier as well. It's not that I don't appreciate the option. This seems far closer to what DocumentDB should have been earlier on. Though tbh, I think Storage Tables are already pretty useful. [1] https://docs.microsoft.com/en-us/azure/cosmos-db/introduction https://docs.microsoft.com/en-us/azure/cosmos-db/introductio...
- smithkl42 9y ago
  Azure Table Storage? Uggh. Nasty. I've tried half a dozen times to use them, and every time I've given up. Great for write-only data that you never want to see again. Horrible for real-world querying.
  - dharmashuklaMS 9y ago
    Cosmos DB has native extensibility to support various APIs Azure Table Storage "APIs" is one of them. If you are a Azure Table Storage customers, by virtue of accessing Cosmos DB using the Table Storage API, you can now get all of the capabilities of Cosmos DB incl. automatic indexing, global distribution etc. Your Table Storage queries should be really fast with Cosmos DB since, Cosmos DB supports efficient indexing and query.
  - tracker1 9y ago
    Most of my usage has been mostly predictable single-key lookups, and some limited querying... The amount of data I've needed to put in it has always been fairly limited as well (generally under a million records per collection/table). It's a decent and really inexpensive option depending on your needs.
lobster_johnson 9y ago
Is Cosmos related to the work on Corfu/CorfuDB [2] [1] in any way? [1] https://www.microsoft.com/en-us/research/publication/corfu-a-shared-log-design-for-flash-clusters/ https://www.microsoft.com/en-us/research/publication/corfu-a... [2] https://github.com/CorfuDB/CorfuDB https://github.com/CorfuDB/CorfuDB
- GovindMS 9y ago
  AS Dharma mentioned - Azure Cosmos DB has been many years in the making. Azure Cosmos DB started as “Project Florence” in late 2010 to address developer the pain-points faced by large scale applications inside Microsoft. Observing that the challenges of building globally distributed apps are not a problem unique to Microsoft, in 2015 we made the first generation of this technology available to Azure developers in the form of DocumentDB. The database engine design is inspired on LLAMA http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-... http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-..., Bwtree - > https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.. https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.... and schema-agnostic indexing techniques -> http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf. Please note that these papers are significantly behind the current state of the implementation. The most crucial aspect that these papers dont cover is the integration of the database engine with the larger distributed system components of Cosmos DB including the resource governance, partition management, and the implementation of replication protocol /consistency models etc. Our goal is to publish all of the design specifications including TLA+ specs over time.
- dharmashuklaMS 9y ago
  Azure Cosmos DB is not related to the work on Corfu/CorfuDB.
voellm 9y ago
One of the best parts of the perf SLA is we did it with all Data Encrypted at Rest. I'm biased. I lead security for CosmosDB.
- sargun 9y ago
  Why is encryption at rest difficult? I presume it's all AES (hardware accelerated), with some key derived at system boot time? Are y'all doing encryption in the D/C, or just on the WAN? If you're doing it on the WAN, any luck using MACSEC?
yunong 9y ago
What's the CAP tradeoffs of Cosmos? It's not clear to me looking at the SLA docs.
- aliuy 9y ago
  CAP only talks about the uncommon unhappy path (given a network partition, what is tradeoff between availability and consistency). PACELC theorem builds on CAP to describe that even in the absence of a network partition, there is a trade-off between latency and consistency (in other words, describing the tradeoffs associated with BOTH the common happy path and uncommon unhappy path). Azure Cosmos DB offers 5 well-defined consistency models for you to choose from, so that you can choose the right tradeoffs for a given application or scenario. This way, you aren't stuck choosing between the hard extremes of Strong and Eventual consistency. See: https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb...
- dharmashuklaMS 9y ago
  As the Cosmos DB SLA doc describes, for any of the 5 consistency models the service supports, the service guarantees all the other three guarantees (latency at the 99th percentile, availability and throughput) at 99.99%. One of the benefits of well-defined consistency models is that for a given model, developers can clearly make the tradeoffs between (1) latency vs. consistency, (2) availability vs. consistency and (3) throughput vs. consistency. The service documentation covers some of these tradeoffs. See (1) https://docs.microsoft.com/en-us/azure/documentdb/documentdb-distribute-data-globally https://docs.microsoft.com/en-us/azure/documentdb/documentdb... and (2) https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb... (also check out the references at the end of the page)
yunong 9y ago
What's the CAP tradeoffs of Cosmos? It's not clear to me looking at the SLA docs.
hoodoof 9y ago
Databases is one area that Amazon is way behind Google and Microsoft. DynamoDB is thoroughly awful so good to see some competition.
hoodoof 9y ago
Does it provide search? It's a strange thing, but almost all new database technologies seem to leave search as an afterthought for some later day instead of starting on day one with the assumption that "it's all about search". A database system that doesn't support rich search capabilities is restricted to very limited types of applications. Often search is left unimplemented for years, or perhaps never implemented.
- harigov 9y ago
  It does support search through SQL like queries. You can use existing functions or implement new ones in Javascript. If you want free text search, you would be disappointed, but otherwise it is pretty decent.
  - hoodoof 9y ago
    So half marks on search for Azure Cosmos DB. If free text search is such a hard problem then you'd think that would be even more reason to start with solving that toughest of all problems. If it's a really hard problem then it will be even harder to retrofit later into some system that is already architected and built. A light spanking for the architect. No search would have been a thorough spanking.
    - harigov 9y ago
      The good news is that you can configure all the data to be copied over to Azure Search on a regular basis and then use search capabilities provided by Azure Search. This may sound like a complicated thing to do but the functionality provided by Azure makes it ridiculously easy to configure something like this.
      - hoodoof 9y ago
        Search should be a first class feature of a database not an addon. Every.Single. Time. I have ever needed to "just add on search" it has resulted in deep pain. Nothing you say will convince me that it's just a super easy dance in the daisies to "just do X" or "just do Y" and suddenly its database search heaven. Database application architects need to wise up that the world revolves around search - built in, not add on.
vikestep 9y ago
I can't seem to find the old DocumentDB prices any more, but it seems like it's a lot cheaper now? Also, is User-Defined Performance something new? since last time I looked into DocumentDB you had to pay the monthly RU fee per 10GB disk. One more thing, as someone who went from DocumentDb to Azure Storage (Tables) back in April 2016 because of the higher price, slower queries, and scalability problems, is there anything that may make Cosmos DB a better option?
sargun 9y ago
Does CosmosDB have any relationship to Microsoft Cosmos (http://web.stanford.edu/class/ee380/Abstracts/111026a-Helland-COSMOS.pdf http://web.stanford.edu/class/ee380/Abstracts/111026a-Hellan...)? Or is this another case of Dynamo / DynamoDB?
- GovindMS 9y ago
  Hi ! Sargun, If you see Dharma's detailed reply which consists of papers and history from 2010. This is a different effort with a different focus. Azure Cosmos DB has been many years in the making. Azure Cosmos DB started as “Project Florence” in late 2010 to address developer the pain-points faced by large scale applications inside Microsoft. Observing that the challenges of building globally distributed apps are not a problem unique to Microsoft, in 2015 we made the first generation of this technology available to Azure developers in the form of DocumentDB. Since that time, we’ve been steadily adding new capabilities both in the database engine as well as, larger distributed system components. Azure Cosmos DB is the result. It is the next big leap in globally distributed, at scale, cloud databases. As a part of this release of Azure Cosmos DB, DocumentDB customers, with their data, are automatically Azure Cosmos DB customers. They now have access to the new system and capabilities offered by Azure Cosmos DB today as well as, as we keep evolving the service. The database engine design is inspired on LLAMA http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-... http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-..., Bwtree - > https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.. https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.... and schema-agnostic indexing techniques -> http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf. Please note that these papers are significantly behind the current state of the implementation. The most crucial aspect that these papers dont cover is the integration of the database engine with the larger distributed system components of Cosmos DB including the resource governance, partition management, and the implementation of replication protocol /consistency models etc. Our goal is to publish all of the design specifications including TLA+ specs over time.
jupp0r 9y ago
> something no other database service can offer. Needs to be updated since Spanner was released
rectalogic 9y ago
I don't see CosmosDB on the HIPAA compliance list, anyone know if there are plans to add it? https://www.microsoft.com/en-us/trustcenter/compliance/hipaa https://www.microsoft.com/en-us/trustcenter/compliance/hipaa
- GovindMS 9y ago
  https://azure.microsoft.com/en-us/blog/azure-compliance-documentdb-certified-for-iso-27001-hipaa-and-the-eu-model-clauses/ https://azure.microsoft.com/en-us/blog/azure-compliance-docu...

336 points by andysinclair 9y ago

judah 9y ago

This isn't a new database. This is a rebranding of the generically-named Azure DocumentDB, plus some new features.

sealord 9y ago
Not exactly. DocumentDB was primarily a document store. Cosmos allows you to store graphs and KV pairs as well.
- jchrisa 9y ago
  I was unable to glean from a quick read of the consistency documentation, does CosmosDB support uniqueness and foreign key constraints?
  - sealord 9y ago
    Afraid not - there's no real concept of constraints with CosmosDB.
- aliostad 9y ago
  DocumentDB is KV.
  - rattray 9y ago
    DocumentDB looks like a JSON document store?
    - hoschicz 9y ago
      It is.
- cowardlydragon 9y ago
  um, property graphs are basically document databases with a special "relationships" property. Then you add the graph algorithms. Key-value is a reduction of document storage.
henriksen 9y ago
Not really. It's a new database and is a superset of DocumentDB.
- antonb9 9y ago
  It's also hosted on the Moon, so it's not just globally distributed but planetary distribution as well. If anything happens to Earth, your data will be safe.
  - henriksen 9y ago
    I thought the secondary was located on Mars?
    - antonb9 9y ago
      Elon Musk has already claimed that planet.
- dharmashuklaMS 9y ago
  Azure Cosmos DB has been many years in the making. Azure Cosmos DB started as “Project Florence” in late 2010 to address developer the pain-points faced by large scale applications inside Microsoft. Observing that the challenges of building globally distributed apps are not a problem unique to Microsoft, in 2015 we made the first generation of this technology available to Azure developers in the form of DocumentDB. Since that time, we’ve been steadily adding new capabilities both in the database engine as well as, larger distributed system components. Azure Cosmos DB is the result. It is the next big leap in globally distributed, at scale, cloud databases. As a part of this release of Azure Cosmos DB, DocumentDB customers, with their data, are automatically Azure Cosmos DB customers. They now have access to the new system and capabilities offered by Azure Cosmos DB today as well as, as we keep evolving the service.
  - curiousDog 9y ago
    Does Cosmos DB support distributed transactions like Spanner? Would be nice to see a deeper dive into Transactions like how isolation works etc.

Dimi9909 9y ago

is this similar to DynamoDB in AWS?

jasondc 9y ago

> Latency: 99.99% of <10 ms latencies at the 99th percentile Impressive SLA to guarantee, I'm curious if this will hold up in all random customer workloads that are coming, e.g. updating a lot of fields in a large document (or just a very large insert).

bigtones 9y ago
Agreed - seems like a rebranding in response to Google Cloud Spanner DB announcement a couple of months back. Microsoft's marketing seems to be pushing some of the same outcomes in the ad copy.
Dimi9909 9y ago
this is a little bit hard to believe. Inter region Ping can even take longer than 15ms... I guess this SLA is for eventual consistency model not strong consistency model
- aravindkr1 9y ago
  The latency SLAs are within the same Azure region. You can distribute your data across any of the 30+ regions that Azure is available in. Your apps always read from the local/closest region with the homing APIs.
  - xapata 9y ago
    That didn't answer the question: will all regions be always consistent?
    - GovindMS 9y ago
      We would invite you to explore the consistency levels available in Cosmos DB. As a developer you can choose what makes most sense in distributed scenario. https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb... Eventual is one end of the consistency. But then consistent prefix, session (if you can control) and bounded staleness all can play a role.

chaostheory 9y ago

Is it open source? Why do I care? The same reason I don't use AWS or Google Cloud only datastores: I want to avoid vendor lockin.

cheeze 9y ago
> Is it open source? Probably not > Why do I care? You might not. > The same reason I don't use AWS or Google Cloud only datastores: I want to avoid vendor lockin. Sounds like this isn't the product for you then. Is that a surprise?
- chaostheory 9y ago
  My questions were rhetorical. One reason I post my thoughts here is because companies like MS are on HN. It's useful to know why people don't want to use your product or are hesitant to do so. Besides, MS has been doing a lot of surprising things lately post-Ballmer.
  - obmelvin 9y ago
    This is meant for people who need services and guarantees that can only be provided by a huge infrastructure provider
    - chaostheory 9y ago
      You can say the same for pretty much every other managed datastore service
oedenfield 9y ago
See the news about Azure Database for MySQL and Postgresql https://azure.microsoft.com/en-us/services/postgresql/ https://azure.microsoft.com/en-us/services/postgresql/ https://azure.microsoft.com/en-us/services/mysql https://azure.microsoft.com/en-us/services/mysql
Thaxll 9y ago
Vendor lock in is a bad example, it's not like you're going to move your infrastructure from AWS to Google every 6months. And if you do you will have many more complicated problems than vendor lock in.

martinknafve 9y ago

No backup/restore?

bpicolo 9y ago
They guarantee durability. I imagine that's a part of it? I guess no backup/restore is a problem if you manage to delete all your data, so we'd have to see some docs, heh
- martinknafve 9y ago
  At some point someone will accidentally overwrite or delete data and discover that some days later...
oedenfield 9y ago
Backup is automatic and restore is available within a time frame. https://docs.microsoft.com/en-us/azure/documentdb/documentdb-online-backup-and-restore https://docs.microsoft.com/en-us/azure/documentdb/documentdb...
- martinknafve 9y ago
  > If the data is accidently dropped or corrupted, please contact Azure support within 8 hours Thats sounds less then optimal. :)
  - dharmashuklaMS 9y ago
    For supporting the "oops I accidentally deleted my table/collection/graph - how do I get it back?" scenario, Cosmos DB automatically takes periodic, full backups of all your data. Currently, we restore your backups on demand and its free - you just send a mail to us. In a few months, we will expose an API using which you can restore the data you accidentally deleted yourself.
dharmashuklaMS 9y ago
Cosmos DB does local persistence and replication both within a region and across any number of regions.All data is durable and made highly available via replication. You dont need to take backups or restore them for ensuring durability or availability. See (1) https://docs.microsoft.com/en-us/azure/cosmos-db/introduction https://docs.microsoft.com/en-us/azure/cosmos-db/introductio... and (2) https://docs.microsoft.com/en-us/azure/cosmos-db/introduction#global-distribution https://docs.microsoft.com/en-us/azure/cosmos-db/introductio.... That said, if you need backup/restore for the cases where you accidentally delete your data and want to resurrect it, Cosmos DB automatically takes backups for you periodically.

anand_MSFT 9y ago

See https://www.youtube.com/watch?v=Yfmw7swCtZs https://www.youtube.com/watch?v=Yfmw7swCtZs by Turing Award Winner, Dr. Leslie Lamport, as he talks about Azure Cosmos DB

dmarlow 9y ago

I want a competitor to Google Cloud SQL in Azure.

curiousDog 9y ago
It's called Azure SQL DB (unless you want Mysql, then you'd want IaaS SQL DB)
- dmarlow 9y ago
  With the exception that Azure SQL doesn't horizontally scale across regions/datacenters like Google Cloud SQL does.
  - curiousDog 9y ago
    I don't think Google Cloud SQL does either in a fully managed way. Spanner OTOH does that but it's NewSQL. Traditional sharding has been supported for a while: https://docs.microsoft.com/en-us/azure/sql-database/sql-database-elastic-scale-introduction https://docs.microsoft.com/en-us/azure/sql-database/sql-data.... you can create databases where ever you want.

henriksen 9y ago

Talk about the foundations of Cosmos DB: https://www.youtube.com/watch?v=Yfmw7swCtZs https://www.youtube.com/watch?v=Yfmw7swCtZs

VikingCoder 9y ago

I'd like to see an in-depth comparison with Google Cloud Spanner.

0xFFC 9y ago
Exactly, although cloud is not my best suite, I am so exited. This is serious fight.
afeezaziz 9y ago
Is there a real life case study of people/startup using Cloud Spanner? I am wondering what are the use cases of Spanner that cannot be fulfilled by other Google Cloud Platform products.
- random3 9y ago
  relational model globally distributed ACID transactions 99.999 availability to name a few
  - arosenbaum 9y ago
    Please post link where they talk about transactions - I can't find it in the docs anywhere. Availability SLA is clearly not 5 9's - https://azure.microsoft.com/en-us/support/legal/sla/cosmos-db/v1_0/ https://azure.microsoft.com/en-us/support/legal/sla/cosmos-d...
    - nindalf 9y ago
      random3 is replying to someone asking about Google's Spanner, which does have those transactions.
daxfohl 9y ago
They're very different things. It's like wanting an in-depth comparison between SQL Server and Redis.

dharmashuklaMS 9y ago

Hi, This is Dharma from Azure Cosmos DB team. We are super excited to make the service available today.We published the first of the series of technical blog posts here -> https://azure.microsoft.com/en-us/blog/a-technical-overview-of-azure-cosmos-db/ https://azure.microsoft.com/en-us/blog/a-technical-overview-.... Would love to answer any Cosmos DB questions.

tosh 9y ago
Can you give an overview on how Cosmos differs from Spanner and CockroachDB?
- dharmashuklaMS 9y ago
  There are many significant differences in capabilities, and design approaches between other systems and Cosmos DB. At a very high level. differences are at two levels - the design of the database engine and the larger distributed system. The database engine design is inspired on LLAMA http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-levandoski.pdf http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-..., Bwtree - > https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19dd54bb6c773736a.pdf https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d... and schema-agnostic indexing techniques -> http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf. Please note that these papers are significantly behind the current state of the implementation. The most crucial aspect that these papers dont cover is the integration of the database engine with the larger distributed system components of Cosmos DB including the resource governance, partition management, and the implementation of replication protocol /consistency models etc. Our goal is to publish all of the design specifications including TLA+ specs over time.
daxfohl 9y ago
Are graph ops/queries atomic? i.e. if you run a tree query on a tree-graph, at the same time you're re-parenting a treenode, is there a chance that the node could end up in the result tree twice or zero times? Also, if they're atomic, are they optimistic or pessimistic transactions? Also if they're atomic, does that mean queries done on the write server? (My understanding is that readonly transactions on read-replicas are not supported, or at least they weren't under DocDB). Any lay-programmer insight into what's going on under the hood, or at least performance/atomicity implications, without giving up too much proprietary info, would be appreciated.

willchen 9y ago

Very interesting DB service. If I'm reading the docs right it sounds like you can't do JOINs across documents? https://docs.microsoft.com/en-us/azure/documentdb/documentdb-sql-query#a-idadvancedaadvanced-database-concepts-and-sql-queries https://docs.microsoft.com/en-us/azure/documentdb/documentdb...

extesy 9y ago
Not using DocumentDB API but you can kinda do joins using graph traversal Gremlin API.

rattray 9y ago

I find this product slightly befuddling. It seems like a "just throw all your data in this" kind of database, probably intended for everything but core application relational data (so, good for analytics, messaging, etc). It sounds like the atom-record-sequence model at the heart of it is pretty key, but there's not a lot in the article about what that is and how it works. Is this a well-understood data structure used elsewhere? The project seems very ambitious, and I could see it being used pretty heavily at a lot of companies. Thoughts?

datasage 9y ago
Its not uncommon to in sass stacks to have multiple data stores, each specialized for different use cases. I do see it appealing to have one system that can support each type of use case and able to tune that as needed.

joshuatalb 9y ago

This feels like MS' version of Google's Cloud Spanner that's GA in a few days. Same kind of marketing too.

strmpnk 9y ago
Having evaluated both, I'd say Cloud Spanner is quite a bit behind in some regards. It's not that Spanner itself can't do something but that Cloud Spanner hasn't productized some important features like multi-datacenter failovers. It's certainly coming but CosmosDB (aka. DocumentDB) does a lot of this today (and has been for awhile as this is not entirely new).
- azurezyq 9y ago
  But from Cosmos DB's doc, cross-dc strong consistency seems not even supported. https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb... "Azure Cosmos DB accounts that are configured to use strong consistency cannot associate more than one Azure region with their Azure Cosmos DB account."
  - strmpnk 9y ago
    I didn't claim cross-dc consistency. I said failover, which is shockingly hard to make many competitors do. The key here is that only one DC can take writes but the failover works transparently with your client (also with clear SLAs).
    - lern_too_spel 9y ago
      Why do you need failover if you have global multimaster like Spanner?
      - aliuy 9y ago
        An interesting thing to point out is the current beta for Cloud Spanner does not have multi-region deployments... and instead, allows you to do single-region deployment in your choice of 3 (not >30) regions: https://cloud.google.com/spanner/docs/instance-configuration https://cloud.google.com/spanner/docs/instance-configuration

ahelwer 9y ago

Designed with TLA+! :D Small interview with Leslie Lamport: https://techcrunch.com/2017/05/10/with-cosmos-db-microsoft-wants-to-build-one-database-to-rule-them-all/ https://techcrunch.com/2017/05/10/with-cosmos-db-microsoft-w... Hope Cosmos team releases a whitepaper on their experiences with the language. I'd heard snatches of gossip here and there that TLA+ was used inside Cosmos, but no concrete details. edit: apparently there's also a video of Lamport talking about this https://www.youtube.com/watch?v=L_PPKyAsR3w https://www.youtube.com/watch?v=L_PPKyAsR3w

dmix 9y ago
The effort to formalize the database was apparently led by: > Leslie Lamport the Turing Award winner whose work underpins many of these concepts (and who also wrote the LaTeX document preparation system) and who joined Microsoft Research in 2001 Quote about TLA+: > As Shukla noted, though, his idea here was to build a database system that could last decades. To do this, he also brought in Lamport to teach the team TLA+. Lamport has long had a special interest in how developers spec out their applications. TLA+ is essentially a formal language for doing just that. “When we started out in 2010, we wanted to build a system — a lasting system. This was the database of the future for Microsoft,” Shukla told me. “We try to apply as much rigor to our engineering as we possibly can. […] TLA+ has been wonderful in getting that level of rigor in a team of engineers to set the bar high for quality.” TLA+, Lamport noted, allows you to do the high-level design of a system in a completely formal way — and because it’s done formally, it can be checked for correctness, too (and to be fair, AWS and others also use TLA+ to spec out their distributed systems). “I don’t want to give the impression that TLA+ is great and I’m brilliant. It’s great because it’s almost entirely based on mathematics,” Lamport added.
OriginalJGC 9y ago
Here is a longer version with Dr. Lamport with more details https://www.youtube.com/watch?v=L_PPKyAsR3w&feature=youtu.be https://www.youtube.com/watch?v=L_PPKyAsR3w&feature=youtu.be
Quiark 9y ago
Wow, that's cool. TLA+ is the same formalism that Amazon uses to verify (some of) their cloud services.

dagi3d 9y ago

If I understood it correctly, they mentioned they offer horizontal scalibility for their databases and I wonder how does it work for the graph data model

aravindkr1 9y ago
This is covered in https://docs.microsoft.com/azure/cosmos-db/gremlin-support https://docs.microsoft.com/azure/cosmos-db/gremlin-support. You can specify a partition key for your graphs for scale out, and access vertices and edges using the partition key + item key ("id") like g.V(['USA', 'Seattle']).

tracker1 9y ago

From the intro page[1]... Many of the descriptions comparing to NoSQL are wrong. There are plenty of NoSQL options that have similar features, though it isn't universal, it can and often is there. Cassandra, for example, probably does just as well in multi-zone/dc concurrency. Consistency options are also similarly tunable. Cockroach 1.0 was announced earlier as well. It's not that I don't appreciate the option. This seems far closer to what DocumentDB should have been earlier on. Though tbh, I think Storage Tables are already pretty useful. [1] https://docs.microsoft.com/en-us/azure/cosmos-db/introduction https://docs.microsoft.com/en-us/azure/cosmos-db/introductio...

smithkl42 9y ago
Azure Table Storage? Uggh. Nasty. I've tried half a dozen times to use them, and every time I've given up. Great for write-only data that you never want to see again. Horrible for real-world querying.
- dharmashuklaMS 9y ago
  Cosmos DB has native extensibility to support various APIs Azure Table Storage "APIs" is one of them. If you are a Azure Table Storage customers, by virtue of accessing Cosmos DB using the Table Storage API, you can now get all of the capabilities of Cosmos DB incl. automatic indexing, global distribution etc. Your Table Storage queries should be really fast with Cosmos DB since, Cosmos DB supports efficient indexing and query.
- tracker1 9y ago
  Most of my usage has been mostly predictable single-key lookups, and some limited querying... The amount of data I've needed to put in it has always been fairly limited as well (generally under a million records per collection/table). It's a decent and really inexpensive option depending on your needs.

lobster_johnson 9y ago

Is Cosmos related to the work on Corfu/CorfuDB [2] [1] in any way? [1] https://www.microsoft.com/en-us/research/publication/corfu-a-shared-log-design-for-flash-clusters/ https://www.microsoft.com/en-us/research/publication/corfu-a... [2] https://github.com/CorfuDB/CorfuDB https://github.com/CorfuDB/CorfuDB

GovindMS 9y ago
AS Dharma mentioned - Azure Cosmos DB has been many years in the making. Azure Cosmos DB started as “Project Florence” in late 2010 to address developer the pain-points faced by large scale applications inside Microsoft. Observing that the challenges of building globally distributed apps are not a problem unique to Microsoft, in 2015 we made the first generation of this technology available to Azure developers in the form of DocumentDB. The database engine design is inspired on LLAMA http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-... http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-..., Bwtree - > https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.. https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.... and schema-agnostic indexing techniques -> http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf. Please note that these papers are significantly behind the current state of the implementation. The most crucial aspect that these papers dont cover is the integration of the database engine with the larger distributed system components of Cosmos DB including the resource governance, partition management, and the implementation of replication protocol /consistency models etc. Our goal is to publish all of the design specifications including TLA+ specs over time.
dharmashuklaMS 9y ago
Azure Cosmos DB is not related to the work on Corfu/CorfuDB.

voellm 9y ago

One of the best parts of the perf SLA is we did it with all Data Encrypted at Rest. I'm biased. I lead security for CosmosDB.

sargun 9y ago
Why is encryption at rest difficult? I presume it's all AES (hardware accelerated), with some key derived at system boot time? Are y'all doing encryption in the D/C, or just on the WAN? If you're doing it on the WAN, any luck using MACSEC?

yunong 9y ago

What's the CAP tradeoffs of Cosmos? It's not clear to me looking at the SLA docs.

aliuy 9y ago
CAP only talks about the uncommon unhappy path (given a network partition, what is tradeoff between availability and consistency). PACELC theorem builds on CAP to describe that even in the absence of a network partition, there is a trade-off between latency and consistency (in other words, describing the tradeoffs associated with BOTH the common happy path and uncommon unhappy path). Azure Cosmos DB offers 5 well-defined consistency models for you to choose from, so that you can choose the right tradeoffs for a given application or scenario. This way, you aren't stuck choosing between the hard extremes of Strong and Eventual consistency. See: https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb...
dharmashuklaMS 9y ago
As the Cosmos DB SLA doc describes, for any of the 5 consistency models the service supports, the service guarantees all the other three guarantees (latency at the 99th percentile, availability and throughput) at 99.99%. One of the benefits of well-defined consistency models is that for a given model, developers can clearly make the tradeoffs between (1) latency vs. consistency, (2) availability vs. consistency and (3) throughput vs. consistency. The service documentation covers some of these tradeoffs. See (1) https://docs.microsoft.com/en-us/azure/documentdb/documentdb-distribute-data-globally https://docs.microsoft.com/en-us/azure/documentdb/documentdb... and (2) https://docs.microsoft.com/en-us/azure/documentdb/documentdb-consistency-levels https://docs.microsoft.com/en-us/azure/documentdb/documentdb... (also check out the references at the end of the page)

yunong 9y ago

What's the CAP tradeoffs of Cosmos? It's not clear to me looking at the SLA docs.

hoodoof 9y ago

Databases is one area that Amazon is way behind Google and Microsoft. DynamoDB is thoroughly awful so good to see some competition.

hoodoof 9y ago

Does it provide search? It's a strange thing, but almost all new database technologies seem to leave search as an afterthought for some later day instead of starting on day one with the assumption that "it's all about search". A database system that doesn't support rich search capabilities is restricted to very limited types of applications. Often search is left unimplemented for years, or perhaps never implemented.

harigov 9y ago
It does support search through SQL like queries. You can use existing functions or implement new ones in Javascript. If you want free text search, you would be disappointed, but otherwise it is pretty decent.
- hoodoof 9y ago
  So half marks on search for Azure Cosmos DB. If free text search is such a hard problem then you'd think that would be even more reason to start with solving that toughest of all problems. If it's a really hard problem then it will be even harder to retrofit later into some system that is already architected and built. A light spanking for the architect. No search would have been a thorough spanking.
  - harigov 9y ago
    The good news is that you can configure all the data to be copied over to Azure Search on a regular basis and then use search capabilities provided by Azure Search. This may sound like a complicated thing to do but the functionality provided by Azure makes it ridiculously easy to configure something like this.
    - hoodoof 9y ago
      Search should be a first class feature of a database not an addon. Every.Single. Time. I have ever needed to "just add on search" it has resulted in deep pain. Nothing you say will convince me that it's just a super easy dance in the daisies to "just do X" or "just do Y" and suddenly its database search heaven. Database application architects need to wise up that the world revolves around search - built in, not add on.

vikestep 9y ago

I can't seem to find the old DocumentDB prices any more, but it seems like it's a lot cheaper now? Also, is User-Defined Performance something new? since last time I looked into DocumentDB you had to pay the monthly RU fee per 10GB disk. One more thing, as someone who went from DocumentDb to Azure Storage (Tables) back in April 2016 because of the higher price, slower queries, and scalability problems, is there anything that may make Cosmos DB a better option?

sargun 9y ago

Does CosmosDB have any relationship to Microsoft Cosmos (http://web.stanford.edu/class/ee380/Abstracts/111026a-Helland-COSMOS.pdf http://web.stanford.edu/class/ee380/Abstracts/111026a-Hellan...)? Or is this another case of Dynamo / DynamoDB?

GovindMS 9y ago
Hi ! Sargun, If you see Dharma's detailed reply which consists of papers and history from 2010. This is a different effort with a different focus. Azure Cosmos DB has been many years in the making. Azure Cosmos DB started as “Project Florence” in late 2010 to address developer the pain-points faced by large scale applications inside Microsoft. Observing that the challenges of building globally distributed apps are not a problem unique to Microsoft, in 2015 we made the first generation of this technology available to Azure developers in the form of DocumentDB. Since that time, we’ve been steadily adding new capabilities both in the database engine as well as, larger distributed system components. Azure Cosmos DB is the result. It is the next big leap in globally distributed, at scale, cloud databases. As a part of this release of Azure Cosmos DB, DocumentDB customers, with their data, are automatically Azure Cosmos DB customers. They now have access to the new system and capabilities offered by Azure Cosmos DB today as well as, as we keep evolving the service. The database engine design is inspired on LLAMA http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-... http://db.disi.unitn.eu/pages/VLDBProgram/pdf/research/p853-..., Bwtree - > https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.. https://pdfs.semanticscholar.org/7655/9c6cc259c6ab5baf7bd19d.... and schema-agnostic indexing techniques -> http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf http://www.vldb.org/pvldb/vol8/p1668-shukla.pdf. Please note that these papers are significantly behind the current state of the implementation. The most crucial aspect that these papers dont cover is the integration of the database engine with the larger distributed system components of Cosmos DB including the resource governance, partition management, and the implementation of replication protocol /consistency models etc. Our goal is to publish all of the design specifications including TLA+ specs over time.

jupp0r 9y ago

> something no other database service can offer. Needs to be updated since Spanner was released

rectalogic 9y ago

I don't see CosmosDB on the HIPAA compliance list, anyone know if there are plans to add it? https://www.microsoft.com/en-us/trustcenter/compliance/hipaa https://www.microsoft.com/en-us/trustcenter/compliance/hipaa

GovindMS 9y ago
https://azure.microsoft.com/en-us/blog/azure-compliance-documentdb-certified-for-iso-27001-hipaa-and-the-eu-model-clauses/ https://azure.microsoft.com/en-us/blog/azure-compliance-docu...