jeroendedauw / wikibasequeryengine

Answers Ask queries against a collection of Wikibase entities

Wikibase QueryEngine

On Packagist:

Wikibase QueryEngine is a library that supports running Ask queries against a collection of Wikibase entities.

Recent changes can be found in the release notes.

Note that this is a fork of the original Wikibase Query Engine, which has the wikibase/query-engine package name. This version is ahead of the original, which is no longer actively developed by its original maintainer: Wikimedia Deutchland.

Installation

You can use Composer to download and install this package as well as its dependencies. Alternatively you can simply clone the git repository and take care of loading yourself.

Composer

To add this package as a local, per-project dependency to your project, simply add a dependency on jeroen/query-engine to your project's composer.json file. Here is a minimal example of a composer.json file that just defines a dependency on Wikibase QueryEngine 1.x:

    {
        "require": {
            "jeroen/query-engine": "~1.0"
        }
    }

Manual

Get the Wikibase QueryEngine code, either via git, or some other means. Also get all dependencies. You can find a list of the dependencies in the "require" section of the composer.json file. Load all dependencies and the load the Wikibase QueryEngine library by including its entry point: WikibaseQueryEngine.php.

Running the tests

For tests only

composer test

For style checks only

composer cs

For a full CI run

composer ci

Usage

CLI

To get a list of available CLI commands, execute this in the root directory:

php queryengine

SQLStore internal structure

Table: entities

• id, string: serialization of the entities id
• type, string: type of the entity

Snak tables

All snak tables have the following fields:

• row_id, int
• subject_id, string
• subject_type, string
• property_id, string
• statement_rank, int

The schema definition is dynamically build in StoreSchema.php.

Value snak tables

There is a value snak table per type of data value the store is configured to support.

All data value tables have a set of additional fields that are specific to the type of data value they store. For the types of data value natively supported by the store.

Valueless snak tables

Additional fields:

• snak_type, int: type of the snak, ie "no value"

Authors

Wikibase QueryEngine has been written by Jeroen De Dauw, and by the Wikidata team for the Wikidata project.

Links

• Wikibase QueryEngine on Packagist
• Wikibase QueryEngine on Ohloh
• Wikibase QueryEngine on GitHub
• TravisCI build status

Related projects

• Wikibase
• Semantic MediaWiki

wikibasequeryengine's Issues

Errors on import

https://github.com/wmde/WikibaseQueryEngine/issues/99

Also related to #3

Add integration tests for different value types / DVHandlers

This component still misses tests that run actual queries, risking critical bugs and design issues being unnoticed until a user complains. These tests already exist for 15 months now in wmde/WikibaseQueryEngine#112 and wmde/WikibaseQueryEngine#114, but are still unmerged. I never got enough information to understand what's wrong with these pull requests.

SQLStore exceptions

Database interaction exceptions need to be caught and propagated with a proper exception type.

Only where applicable - at some points we might want to fire error events instead, so the user can determine if execution should be aborted or not.

Do not throw exception on encountering value that cannot be stored

Need to be able to store the rest of the entity if so desired

throw new InvalidArgumentException( 'Units other than "1" are not yet supported.' );

in QuantityHandler