PGroonga 3.2.1 - Multilingual fast full text search

Posted on 2024-07-10 by PGroonga project
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Hi,

PGroonga 3.2.1 has been released!

This release adds support for WAL resource manager!

With the WAL resource manager support, you can solve the following problems with the general WAL approach in PGroonga < 3.2.1:

  • You need to remove old WAL manually to avoid unlimited storage usage
  • You need to use additional mechanism to apply WAL in background
  • You need to recover from a crash after PostgreSQL started

See also the following document how to use this feature: Streaming replication by WAL resource manager

Note that you need PostgreSQL 15 or later because this is based on custom WAL resource manager feature that is available since PostgreSQL 15.

If you're interesting in how to implement the WAL resource manager, see also the following blog post:

Japanese: How to implement the PGroonga's WAL resource manager

English: Google Translate of the post

About PGroonga

PGroonga is a PostgreSQL extension that makes PostgreSQL fast full text search platform for all languages! It's released under PostgreSQL license.

There are some PostgreSQL extensions that improves full text search feature of PostgreSQL such as pg_trgm^1.

pg_trgm doesn't support languages that use non-alphanumerics characters such as Japanese and Chinese.

PGroonga supports all languages, provides rich full text search related features and is very fast. Because PGroonga uses Groonga^2 that is a full-fledged full text search engine as backend.

See the following benchmark results for performance:

  • Benchmark result for PGroonga, textsearch and pg_trgm with English Wikipedia https://pgroonga.github.io/reference/pgroonga-versus-textsearch-and-pg-trgm.html
  • Benchmark result for PGroonga and pg_bigm with Japanese Wikipedia https://pgroonga.github.io/reference/pgroonga-versus-pg-bigm.html

PGroonga also supports JSON search. You can use each value for condition. You can also perform full text search against all texts in JSON like textsearch in PostgreSQL.

Changes

Here are highlights in PGroonga 3.2.1:

  • Added support for WAL resource manager
  • Added support for downgrading by using ALTER EXTENSION ... UPDATE
  • Added support for Ubuntu 24.04 (Noble Numbat)
  • Added support for typo-tolerance search
  • Fixed some crash bugs

See also the 3.2.1 release note for full changes.

Usage

You can use PGroonga without full text search knowledge. You just create an index and puts a condition into WHERE:

CREATE INDEX index_name ON table USING pgroonga (column);
SELECT * FROM table WHERE column &@~ 'PostgreSQL';

You can also use LIKE to use PGroonga. PGroonga provides a feature that performs LIKE with index. LIKE with PGroonga index is faster than LIKE without index. It means that you can improve performance without changing your application that uses the following SQL:

SELECT * FROM table WHERE column LIKE '%PostgreSQL%';

Are you interested in PGroonga? Please install^4 and try tutorial^5. You can know all PGroonga features.

You can install PGroonga easily. Because PGroonga provides packages for major platforms. There are binaries for Windows.

Thanks,