README

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.

jeroen / query-engine

Maintainers

Details