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Latest revision as of 11:27, 20 April 2026

This page demonstrates the mw.neowiki Lua API for accessing NeoWiki structured data from templates and modules.

The examples use Module:NeoWikiDemo, a demo module included with NeoWiki.

Reading Property Values

mw.neowiki.getValue() returns a single scalar value. mw.neowiki.getAll() returns all values as a table.

Property	getValue	getAll
Founded at	2005	2005
Websites	https://acme.example	https://acme.example
Products (relations)	Acme Anvil	Acme Anvil, Acme Rocket, Acme TNT

Full Subject Data

mw.neowiki.getMainSubject() returns all data for a Subject as a Lua table, enabling templates to render complete data views.

Professional Wiki

Property	Type	Value(s)
Websites	url	https://professional.wiki, https://wikibase.consulting
Products	relation	NeoWiki, ProWiki
Founded at	number	2019
World domination progress	number	42
Status	select	o1demo1aaaaaaa1

ACME Inc

Property	Type	Value(s)
Websites	url	https://acme.example
Products	relation	Acme Anvil, Acme Rocket, Acme TNT
Is public	boolean	true
Offices	relation	ACME Amsterdam HQ, ACME Vienna Office
Departments	relation	ACME Engineering, ACME Sales, ACME Operations
Headquarters	relation	ACME Amsterdam HQ
Status	select	o1demo1aaaaaaa1
World domination progress	number	42
Founded at	number	2005

Child Subjects

mw.neowiki.getChildSubjects() returns all non-main Subjects on a page.

Child subjects on ACME Inc: No child subjects

Running Cypher Queries

mw.neowiki.query() runs a read-only Cypher query and returns each row as a Lua table keyed by the RETURN aliases. Use it when a single-property lookup is not enough — for example to join Subjects, sort results, or list all Subjects of a given type.

Listing all Companies

MATCH (n:Company) RETURN n.name, n.id

n.id	n.name
s1demo5sssssss1	Professional Wiki GmbH
s1demo1aaaaaaa1	ACME Inc
s1demo5ssssssz1	Hallo Welt! GmbH
sEpjeGi3EjWM9dw	Main Pagegfsdgt
sEq1P1iwqG1s4UP	Fggxftgx
sEr2axw2QTXhVLk	KMA Knowledge Management Associates
s1demo1aaa2aaa1	ACME Inc. 2

Parameterised query: Products available since a given year

Templates should always pass values via the params table instead of concatenating into the query string.

nw.query(
    'MATCH (n:Product) WHERE n.`Available since` >= $year ' ..
        'RETURN n.name AS name, n.`Available since` AS year ORDER BY year',
    { year = 2010 }
)

Products available since 2010:

name	year
Acme Rocket	2010
Foo	2010
Acme TNT	2015
Foo	2015
ProWiki	2022
NeoWiki	2026
Test Subject	2026
Exampleproduct	2026

Inspecting a Schema

mw.neowiki.getSchema() returns a Schema definition as a Lua table, including all property names, types, and type-specific attributes. This enables templates to render or validate any schema without hardcoding property names.

Company

Name	Type	Required	Details
Founded at	number	No
Websites	url	No	multiple: true
Main product	relation	No	targetSchema: Product, relation: Has main product
Products	relation	No	targetSchema: Product, relation: Has product
Departments	relation	No	targetSchema: Department, relation: Has department
Offices	relation	No	targetSchema: Office, relation: Has office
Headquarters	relation	No	targetSchema: Office, relation: Has headquarters
Status	select	Yes	options: Active, Inactive, Acquired, Dissolved
World domination progress	number	No
Is public	boolean	No

Employee

Name	Type	Required	Details
LegalName	text	No
WorkEmail	text	No
EmploymentFte	number	No	min: 0, max: 100
Skills	text	No	multiple: true, uniqueItems: true
Employer	relation	No	targetSchema: Company, relation: Employer

Module Source

The demo module uses these mw.neowiki functions:

local nw = require( 'mw.neowiki' )

-- Read a single value (always returns a scalar or nil)
nw.getValue( 'Founded at' )             --> 2005
nw.getValue( 'Products' )               --> "Foo" (first value only)

-- Read all values (always returns a 1-indexed table or nil)
nw.getAll( 'Products' )                 --> { "Foo", "Bar", "Baz" }

-- Get full subject data
local s = nw.getMainSubject( 'ACME Inc' )
s.id, s.label, s.schema, s.statements

-- Get child subjects
local children = nw.getChildSubjects( 'ACME Inc' )

-- Run a read-only Cypher query
local rows = nw.query(
    'MATCH (n:Product) WHERE n.`Available since` >= $year RETURN n.name, n.`Available since`',
    { year = 2010 }
)

See Module:NeoWikiDemo for the full source.

@@ Line 34: / Line 34: @@
 Child subjects on [[ACME Inc]]: {{#invoke:NeoWikiDemo|children|ACME Inc}}
+== Running Cypher Queries ==
+<code>mw.neowiki.query()</code> runs a read-only Cypher query and returns each row as a Lua table keyed
+by the <code>RETURN</code> aliases. Use it when a single-property lookup is not enough — for example
+to join Subjects, sort results, or list all Subjects of a given type.
+=== Listing all Companies ===
+<syntaxhighlight lang="cypher">
+MATCH (n:Company) RETURN n.name, n.id
+</syntaxhighlight>
+{{#invoke:NeoWikiDemo|query|MATCH (n:Company) RETURN n.name, n.id}}
+=== Parameterised query: Products available since a given year ===
+Templates should always pass values via the <code>params</code> table instead of concatenating into the query string.
+<syntaxhighlight lang="lua">
+nw.query(
+    'MATCH (n:Product) WHERE n.`Available since` >= $year ' ..
+        'RETURN n.name AS name, n.`Available since` AS year ORDER BY year',
+    { year = 2010 }
+)
+</syntaxhighlight>
+Products available since 2010: {{#invoke:NeoWikiDemo|productsFoundedSince|2010}}
+== Inspecting a Schema ==
+<code>mw.neowiki.getSchema()</code> returns a Schema definition as a Lua table, including all property names, types, and type-specific attributes. This enables templates to render or validate any schema without hardcoding property names.
+=== Company ===
+{{#invoke:NeoWikiDemo|schema|Company}}
+=== Employee ===
+{{#invoke:NeoWikiDemo|schema|Employee}}
 == Module Source ==
@@ Line 55: / Line 95: @@
 -- Get child subjects
 local children = nw.getChildSubjects( 'ACME Inc' )
+-- Run a read-only Cypher query
+local rows = nw.query(
+    'MATCH (n:Product) WHERE n.`Available since` >= $year RETURN n.name, n.`Available since`',
+    { year = 2010 }
+)
 </syntaxhighlight>