Talk:H2 (database)

What is Going on with H2 Today???
What is the current status of H2?

For a project w/ so much interest, the WP entry is rather sparse, outdated, and contains a disproportionate discussion of what is an issue common to all transactional RDBMS (Challenges affecting durability of relational databases). Does anyone who uses H2, or who is part of the project want to contribute anything?

I would like to know more about it's use, how it can be used inside of LibreOffice/OpenOffice to replace the default RDBMS engine, performance comparison w/ MySQL/MariaDB, PostgreSQL, the other embedded Java databases, as well as feature comparisons.

At a minimum, someone could have just cut-and-pasted the feature list (http://www.h2database.com/html/features.html#feature_list) for the introduction and said a few words about each bullet point.

This article doesn't really do a very good job describing H2, where it is used, why it is used. It seems to get a few edits a year, but is missing a crap-ton of H2 features, options, and other distinguishing features.

Some questions after browsing the WP article and H2 website

 * Which subset of SQL is used today? What is missing?
 * Does H2 have a non-JDBC API as well?
 * Is the RBAC by table, row, column?
 * How does the native full text search implementation perform?
 * What are it's limits (i.e. is there a maximum data length, what encoding does it support, what languages/UTF8 ranges are supported?
 * Can you show examples or describe a use case for it? What are its salient features?
 * Do you need to install Lucene to use the Lucene based full text?
 * The discussion on high availability is absurdly scant, and doesn't state why you can only enable it AFTER a failure.
 * Under "utilities" it would be nice to know what other GUI DB design tools could work w/ H2 (can they create tables, users, design or reverse engineer DBs w/ ERDs?
 * What sort of geographic/topology data types are supported? (q.v. https://www.h2database.com/html/datatypes.html#geometry_type, http://www.h2database.com/html/advanced.html#spatial_features)
 * For that matter, what data types are supported at all?
 * Does it have polymorphic data types support like MariaDB?
 * Are there any graph databases which use/embed H2?
 * Does H2 have any support of indexed links so you could use it as a basic graph DB (i.e. traverse by linkage, not by SQL)
 * Does H2 support binary data, and to what extent? Does it recognize the signature of different media types?  Is there support for reading in a library of media?
 * Is there XML support, and, if so, to what extent?
 * Does it support REGEX?
 * Does it store objects? (q.v. https://www.h2database.com/html/datatypes.html#other_type, also see https://www.h2database.com/html/datatypes.html#array_type)
 * Does it use/support JSON? (q.v. https://www.h2database.com/html/datatypes.html#json_type)
 * (How) can you do recursive queries? Where is this useful? (q.v. http://www.h2database.com/html/advanced.html#recursive_queries)
 * Can users define their own datatypes?
 * How are stored procedures implemented by users?
 * Are triggers supported?
 * What sort of DB storage optimizations are available? (q.v. http://www.h2database.com/html/advanced.html#file_system)
 * What are H2's compatibility modes?
 * What are the limitations and advantage in using in embedded mode vs. client-server mode (assume single user w/ DB as part of an application, not as a general client-server set up where the DB is serving multiple users)
 * How much data can H2 handle (i.e. maximum table width, size, # rows) (q.v. http://www.h2database.com/html/advanced.html#limits_limitations)
 * Does H2 support different DB engines?
 * Does H2 have features which would make it useful for OLAP?

NB: I am just beginning to look at using H2. I have been using MySQL/MariaDB for a decade and a half and don't consider myself knowledgeable enough about MariaDB/MySQL to make much in the way of contributions to that WP article. I would love to be able to answer my own questions ehre, but that will take some time, and there is much to be said of real-world hands-on experience when writing about software. I hope that these questions can help stimulate someone to flushing out a more robust article.

Minor Bug
This References Link indicates it was added next year. — Preceding unsigned comment added by Jstdadd (talk • contribs) 21:02, 13 December 2013 (UTC)

Criticism section needed
H2 DB currently has a tricky problem with database corruption, allegedly when the system is under high loads and the disk storage space deplates quickly. H2 has basic robustness problems underlying this issue and there is only a promise of bugfix in the upcoming version. The problem affects at least one IT-security vendor within the server-side DB of their centralized management solution, since the beginning of summer 2011, at least. 82.131.210.163 (talk) 14:35, 8 February 2012 (UTC)


 * Do you have a link to a bug report for this? twimoki (talk) 05:23, 9 February 2012 (UTC)
 * Has this been fixed in the last 8 years?!? — Preceding unsigned comment added by 2601:441:4D80:93F0:392B:3C8E:9CDA:3BBD (talk) 01:47, 15 October 2020 (UTC)