How reliable is h2 database?
How reliable is h2 database? [closed]
In 2010 we switched away from H2 to MySQL for our large[r] corporate database shards. The biggest reason was that the internal H2 engine is single threaded. When large, unoptimized queries are running across our databases with 100s of thousands or millions of rows, all other database operations would stop. See the H2 documentation for more info. The row locking of H2 seems relatively immature compared to MySQL or Postgres.
In addition, MySQL and Postgres also provide replication mechanisms instead of rolling your own. This also allows us to backup our database system "live" from the slave instead of blocking a H2 database while we dump it.
Lastly, although I've not run this performance test, I suspect that although H2 is lightening fast for small to mid sized databases, as you increase the database size and especially the number of concurrent queries, MySQL and Postgres will start to equal and then best its overall performance -- especially looking at query time distribution.
We continue to use H2 for boutique, in memory, and test databases very successfully. Thanks much to Thomas for it!
H2 is a terrific database engine. After we solved a problem not related to H2, we switched from PostgreSQL and MySQL (both still supported) to H2. H2 became our primary database choice.
Speed is the main reason, but there are others: the embedded mode is amazing and gives us the flexibility to install the software in a portable device, even share the database on the cloud, let's say via Dropbox!
We don't use many features, because we are "persistent dependent" through "Datanucleus" (no triggers, procedures, etc), but our app is complex enough to push the H2! And it delivers flawlessly.
Will this pace be kept?
That's the plan.
will it be supported by opensource community for long term?
It's hard to predict the future, I guess that's why nobody replied to your question yet :-) I'm sure it will be supported, because enough people use it. H2 is used in many (open source and commercial) products. Quite many regularly reply to questions in the mailing list. H2 currently doesn't have many committers, one reason is that the users are generally happy with its features, and because the current development speed is fast enough and the code quality is good enough.
Subscription based support is currently not available, but that's planned for the future (it always was the plan to provide commercial support at some point). The reason it is not yet available is that H2 doesn't yet have enough market share to start a company.