Cheatsheets:SPARQL - Revision history

SeedBot: Standardize: add copy button to block code snippets

2026-08-23T09:45:54Z

Standardize: add copy button to block code snippets

Rongzhou at 07:55, 23 August 2026

2026-08-23T07:55:05Z

← Older revision		Revision as of 07:55, 23 August 2026
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	{{Cheatsheet}}		{{Cheatsheet}}

	If you are new to SPARQL, see [[FOSS:SPARQL\|SPARQL101]]		If you are new to SPARQL, see [[FOSS:SPARQL\|SPARQL101]].

	<blockquote>		<blockquote>

Rongzhou at 07:54, 23 August 2026

2026-08-23T07:54:32Z

← Older revision		Revision as of 07:54, 23 August 2026
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	{{Cheatsheet}}		{{Cheatsheet}}

			If you are new to SPARQL, see [[FOSS:SPARQL\|SPARQL101]]

	<blockquote>		<blockquote>
	~~All examples~~ run as-is against the public Wikidata endpoint <syntaxhighlight lang="text" inline>https://query.wikidata.org/sparql</syntaxhighlight>. Querying another Wikibase instance is similar, but small query adjustments may be necessary depending on how each instance is set up. See the documentation for your target instance for more info.		Examples featured in this cheatsheet run as-is against the public Wikidata endpoint <syntaxhighlight lang="text" inline>https://query.wikidata.org/sparql</syntaxhighlight>. Querying another Wikibase instance is similar, but small query adjustments may be necessary depending on how each instance is set up. See the documentation for your target instance for more info.
			</blockquote>

	~~If you are new to SPARQL and would like a quick 101, see~~		== Basic example ==
	~~[https://www.wikidata.org/wiki/Wikidata:SPARQL_tutorial Wikidata SPARQL tutorial].~~
	~~</blockquote>~~
	== Basic example: ==

	Natural language question:		Natural language question:

Rongzhou at 14:21, 19 August 2026

2026-08-19T14:21:23Z

← Older revision		Revision as of 14:21, 19 August 2026
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	{{Cheatsheet}}		{{Cheatsheet}}

	~~SPARQL 1.1 quick syntax reference — for people who already know what SPARQL is~~		<blockquote>
	~~and need reminders on syntax.~~ All examples run as-is against the public		All examples run as-is against the public Wikidata endpoint <syntaxhighlight lang="text" inline>https://query.wikidata.org/sparql</syntaxhighlight>. Querying another Wikibase instance is similar, but small query adjustments may be necessary depending on how each instance is set up. See the documentation for your target instance for more info.
	Wikidata endpoint <syntaxhighlight lang="text" inline>https://query.wikidata.org/sparql</syntaxhighlight>. Querying another Wikibase instance is similar, but small query adjustments may be necessary depending on how each instance is set up. See the documentation for your target instance for more info.

	If you are new to SPARQL and would like a quick 101, see		If you are new to SPARQL and would like a quick 101, see
	[https://www.wikidata.org/wiki/Wikidata:SPARQL_tutorial Wikidata SPARQL tutorial].		[https://www.wikidata.org/wiki/Wikidata:SPARQL_tutorial Wikidata SPARQL tutorial].
			</blockquote>
	== Basic example: ==		== Basic example: ==

SeedBot: Gotchas with integrated examples inside blockquotes: FILTER NOT EXISTS vs MINUS (both queries, identical normal-case results), property-path intermediate-variable gotcha (path form vs explicit form) (via update-page on MediaWiki MCP Server)

2026-08-19T13:47:12Z

Gotchas with integrated examples inside blockquotes: FILTER NOT EXISTS vs MINUS (both queries, identical normal-case results), property-path intermediate-variable gotcha (path form vs explicit form) (via update-page on MediaWiki MCP Server)

@@ Line 399: / Line 399: @@
 </syntaxhighlight>
-<blockquote>'''Gotcha:''' an unbound variable in a FILTER makes the row fail (unbound ≠ false) — guard with <syntaxhighlight lang="sparql" inline>BOUND()</syntaxhighlight> or restructure with OPTIONAL.</blockquote>
+<blockquote>'''Gotcha:''' an unbound variable in a FILTER makes the row fail (unbound ≠ false) — guard with <syntaxhighlight lang="sparql" inline>BOUND()</syntaxhighlight> or restructure with OPTIONAL.
 The unbound FILTER fails silently. This returns '''no rows''', although
@@ Line 433: / Line 433: @@
 Albert Einstein
 </syntaxhighlight>
 == UNION, OPTIONAL, MINUS ==
@@ Line 539: / Line 540: @@
 </syntaxhighlight>
-<blockquote>'''Gotcha:''' <syntaxhighlight lang="sparql" inline>FILTER NOT EXISTS</syntaxhighlight> differs from <syntaxhighlight lang="sparql" inline>MINUS</syntaxhighlight> when variables are unbound — prefer MINUS for set-difference semantics.</blockquote>
+<blockquote>'''Gotcha:''' <syntaxhighlight lang="sparql" inline>FILTER NOT EXISTS</syntaxhighlight> and <syntaxhighlight lang="sparql" inline>MINUS</syntaxhighlight> usually give the same result, but differ when a variable is unbound — prefer MINUS for set-difference semantics.
 == Property paths ==
@@ Line 593: / Line 628: @@
 (These are sub-subclasses: Lapponian Herder → herding dog → dog.)
-<blockquote>'''Gotcha:''' variables used only inside a property path (e.g. <syntaxhighlight lang="sparql" inline>?s wdt:P279/wdt:P279 ?o</syntaxhighlight>) cannot be selected.</blockquote>
+<blockquote>'''Gotcha:''' a variable that appears only inside a path is not bound, so it cannot be selected.
 == Aggregates ==
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 </syntaxhighlight>
-<blockquote>'''Gotcha:''' aggregates need GROUP BY for every non-aggregated variable. Forgetting one is a '''query error''', not a wrong result.</blockquote>
+<blockquote>'''Gotcha:''' aggregates need GROUP BY for every non-aggregated variable. Forgetting one is a '''query error''', not a wrong result.
 Missing GROUP BY for <syntaxhighlight lang="sparql" inline>?animalLabel</syntaxhighlight>:
@@ Line 724: / Line 798: @@
 ERROR: Bad aggregate — every non-aggregated variable needs GROUP BY
 </syntaxhighlight>
 == Subqueries ==

Rongzhou: /* Running example: */

2026-08-19T13:45:36Z

Running example:

← Older revision		Revision as of 13:45, 19 August 2026
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	[https://www.wikidata.org/wiki/Wikidata:SPARQL_tutorial Wikidata SPARQL tutorial].		[https://www.wikidata.org/wiki/Wikidata:SPARQL_tutorial Wikidata SPARQL tutorial].

	== ~~Running~~ example: ==		== Basic example: ==

	Natural language question:		Natural language question:

Rongzhou: /* OPTIONAL, UNION, MINUS */ rewording

2026-08-19T13:43:19Z

OPTIONAL, UNION, MINUS: rewording

← Older revision		Revision as of 13:43, 19 August 2026
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	== UNION, OPTIONAL, MINUS ==		== UNION, OPTIONAL, MINUS ==

			{\| class="wikitable"
			! Keyword !! Meaning
			\|-
			\| UNION \|\| pattern A '''OR''' pattern B (the default between patterns is AND, not OR)
			\|-
			\| OPTIONAL \|\| declare a statement optional: do not omit a result entity because it has no value for statement
			\|-
			\| MINUS \|\| negation: search for things that do '''NOT''' satisfy a given pattern
			\|}

	The default between triple patterns is '''AND (join)''': the same variable must		The default between triple patterns is '''AND (join)''': the same variable must
	satisfy all patterns. ~~This~~ returns only dogs that also have an image:		satisfy all patterns. The following query returns only dogs that also have an image:

	<syntaxhighlight lang="sparql">		<syntaxhighlight lang="sparql">
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	\|}		\|}

	~~{\| class="wikitable"~~		Use '''OPTIONAL''' when you would like to find out something when data is available, but don't care if the data is missing — Einstein (died 1955) vs Obama (alive); ?deathLabel is unbound
	~~! Keyword !! Meaning~~
	\|-
	~~\| OPTIONAL \|\| left join: keep the row, leave the variable unbound when absent~~
	\|-
	~~\| UNION \|\| alternatives (the default between patterns is AND, not OR)~~
	\|-
	~~\| MINUS \|\| remove rows that match the pattern~~
	\|}

	'''OPTIONAL''' — Einstein (died 1955) vs Obama (alive); ?deathLabel is unbound
	for Obama:		for Obama:

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	</syntaxhighlight>		</syntaxhighlight>

	'''MINUS''' — Nobel laureates ~~minus the French ones~~:		If you do not declare '''OPTIONAL''', Barack Obama will not appear in the results, as there is logically no date of death on his record.

			Use '''MINUS''' when you would like to find out about things that are/have NOT something

			E.g., '''non-French''' Nobel laureates:

	<syntaxhighlight lang="sparql">		<syntaxhighlight lang="sparql">

Rongzhou: /* OPTIONAL, UNION, MINUS */

2026-08-19T13:33:02Z

OPTIONAL, UNION, MINUS

← Older revision		Revision as of 13:33, 19 August 2026
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	</syntaxhighlight>		</syntaxhighlight>

	== OPTIONAL~~, UNION~~, MINUS ==		== UNION, OPTIONAL, MINUS ==

	The default between triple patterns is '''AND (join)''': the same variable must		The default between triple patterns is '''AND (join)''': the same variable must

Rongzhou: /* OPTIONAL, UNION, MINUS */ rewording

2026-08-19T13:31:40Z

OPTIONAL, UNION, MINUS: rewording

← Older revision		Revision as of 13:31, 19 August 2026
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	</syntaxhighlight>		</syntaxhighlight>

	Because of AND, you ~~cannot simply~~ "or" ~~two patterns — nothing is simultaneously~~		Because the default is AND, when you would like to find something that is/has either A "or" B, you need to use '''UNION'''
	~~a dog and a cat. The~~ UNION ~~version works (running example); without UNION you~~
	~~get nothing:~~

	{\| class="wikitable"		{\| class="wikitable"
	! Without UNION (AND) !! With UNION		! Without UNION (AND) !! With UNION

SeedBot: Gotchas as negative/positive pairs; OPTIONAL/UNION/MINUS opens with AND default + example; property paths rebuilt on P279 subclass hierarchy (direct 314 vs transitive 511, same property both tables) (via update-page on MediaWiki MCP Server)

2026-08-19T13:26:57Z

Gotchas as negative/positive pairs; OPTIONAL/UNION/MINUS opens with AND default + example; property paths rebuilt on P279 subclass hierarchy (direct 314 vs transitive 511, same property both tables) (via update-page on MediaWiki MCP Server)

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