Groonga 5.1.2 has been released

Groonga 5.1.2 has been released!

How to install: Install


Here are important changes in this release:

  • Improved performance for sequential scan search. It'll be a few times faster.
  • Added configuration feature. You can set/get configuration items per database. They are persistent.
  • Added alias feature. It'll be useful for schema management.
  • Fixed and improved mruby. Now, mruby is enough stable for use cases by Groonga.

Performance improvements

In the previous release, sequential search of regular expression match performance was improved. In this release, more conditions such as constant (true, 29 and so on) and binary operation (COLUMN == 29, COLUMN > 29 and so on) are supported.

These sequential search improvements will make Groonga a few times faster.

In the future release, query planner will be improved. The current query planner uses all available indexes. But some queries can be executed faster by using sequential scan instead of index search. The current query planner will use both indexes and sequential scan in the future.


You can manage configuration items per database. Configuration items are persistent. You can use them after Groonga restarts.

Here are commands to manage configuration items:


Alias adds other name to an existing object (table, column, function, command and so on). It means that you can refer the same object by multiple names.

It's useful to change schema without downtime. It's also useful to provide backward compatibility. See the above document for details.


Groonga started embedding mruby about 2 years ago. Groonga increases mruby use cases such as command line tool grndb and sharding.

Groonga project feeds back to mruby when Groonga project finds problems of mruby. mruby accepts all bug fixes and improvements by Groonga project.

Now, mruby is enough stable for use cases by Groonga. In the near future, Groonga project will mark mruby as required module and use mruby for more situations.


See Release 5.1.2 2016-01-29 about detailed changes since 5.1.1.

Let's search by Groonga!