This document describes SPARQL 1.2 Update, an update language for RDF graphs. It uses a syntax derived from the SPARQL Query Language for RDF. Update operations are performed on a collection of graphs in a Graph Store. Operations are provided to update, create, and remove RDF graphs in a Graph Store.
This specification is published by the RDF Star Working Group as part of the update of specifications for format and errata.
SPARQL 1.2 Update is intended to be a standard language for specifying and executing updates to RDF graphs in a Graph Store.
SPARQL 1.2 Update provides the following facilities:
This document is particularly related to the following other specification documents:
SPARQL 1.2 Update is a companion language and envisaged to be used in conjunction with the SPARQL 1.2 Query language. The present document refers to the grammar and several definitions from the SPARQL 1.2 Query language specification.
The SPARQL 1.2 Graph Store HTTP Protocol specification employs the HTTP protocol to perform update operations using standard HTTP methods, such as PUT and DELETE. While providing a simple and well known API, it is necessarily restricted in its operations due to the limited set of methods in the HTTP protocol. In contrast, SPARQL 1.2 Update permits multiple modifications in a single operation, and can use complex SPARQL queries for constructing data to be inserted, or choosing data to be deleted. Also, the use of an update language facilitates operations over proprietary APIs and connections that may not involve HTTP.
The SPARQL 1.2 Protocol for RDF specification describes a means of conveying SPARQL 1.2 Query and SPARQL 1.2 Update operations from clients to a SPARQL query processing service, and for returning appropriate results. Together with the SPARQL 1.2 Query and SPARQL 1.2 Update (this document) specifications, these form an alternative to the SPARQL 1.2 Graph Store HTTP Protocol with comprehensive, though more complex functionality.
The operations in this document contain language forms describing their use. These are meant as illustrative forms of the formal grammar described in the SPARQL 1.2 Query document. Any discrepancies between the language forms in this document and the grammar in SPARQL 1.2 Query will defer to the formal grammar in SPARQL 1.2 Query.
Language forms are shown informally in this document as for instance:
( WITH IRIref )?
( ( DeleteClause InsertClause? ) | InsertClause )
( USING ( NAMED )? IRIref )*
WHERE GroupGraphPattern
Unlike other forms of EBNF where square brackets denote optionality, here [] is used for blank nodes, as in SPARQL Query. | is used to denote
alternatives, () is used for grouping terms, ? indicates 0 or 1 occurrence of a term, * indicates 0 or more occurrences, and + indicates
1 or more occurrences.
BOLD indicates language keywords. Italics indicate syntactic items defined in the SPARQL 1.2 Query Grammar, where we occasionally refer to productions by links. Unitalicized text indicates a local term that will
have a more complex (and exact) definition in the formal grammar.
Example update requests are shown as follows:
PREFIX dc: <http://purl.org/dc/elements/1.1/>
INSERT { <http://example/egbook> dc:title "This is an example title" } WHERE {}
PREFIX definitions and the syntax for IRIs in update requests in
general follow the same conventions as in the [[[SPARQL12-QUERY]]].
Data is shown in Turtle syntax as follows:
PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX : <http://example.org/books/> :book0 dc:title "SPARQL Tutorial" .
When this document uses the words MUST, MUST NOT, SHOULD, SHOULD NOT, and MAY, and the words appear as emphasized text, they must be interpreted as described in [[RFC2119]].
The following terms are also in use throughout this document:
The following terms are also used in this document as defined in the SPARQL 1.2 Query Language:
QuadPattern — A syntactic construct that refers to a set of triple patterns, similar to
ConstructTriples, but potentially involving the GRAPH keyword to indicate that a
set of triples is to be inserted into/deleted from a named graph.QuadData — A QuadPattern without variables.GroupGraphPattern — A syntactic construct for referring to a set of triples, possibly with
complex constraints.A Graph Store is a mutable container of RDF graphs managed by a single service. Similar to an RDF Dataset operated on by the [[[SPARQL12-QUERY]]], a Graph Store contains one (unnamed) slot holding a default graph and zero or more named slots holding named graphs. Operations MAY specify graphs to be modified, or they MAY rely on a default graph for that operation. Unless overridden (for instance, by the SPARQL protocol), the unnamed graph for the store will be the default graph for any operations on that store. Depending on implementation, the unnamed graph MAY refer to a separate graph, a graph describing the named graphs, a representation of a union of other graphs, etc.
Unlike an RDF Dataset, named graphs can be added to or deleted from a Graph Store. A Graph Store needs not be authoritative for the graphs it contains. That means a Graph Store can keep local copies of RDF graphs defined elsewhere on the Web and modify those copies independently of the original graph.
In the simple case where there is one unnamed graph and no named graphs, SPARQL 1.2 Update can be used as a graph update language (as opposed to a Graph Store update language).
The information how a Graph Store is accessed is defined in the protocol and Graph Store protocol specs. A Graph Store is accessible by either an update service (cf. protocol) or via the Graph Store protocol (cf. Graph Store protocol). In either case the Graph Store is hidden behind the service, making it accessible via the URI of a SPARQL update service or via a URI that responds to the Graph Store protocol.
A formal definition for Graph Stores and how SPARQL 1.2 Update affects them is described in the SPARQL 1.2 Update Formal Model section.
A service (often referred to by the informal term SPARQL endpoint) that accepts and processes update requests is referred to as an update service. There is no presumption that the Graph Store managed by an update service exactly corresponds to any RDF Dataset offered by some query service. A query service MAY offer an RDF Dataset formed from graphs that are part of an update service's Graph Store. The graphs in the query service's RDF Dataset MAY be a subset of the graphs in the update service's Graph Store. Furthermore, the query service's RDF Dataset and the update service's Graph Store MAY use different names for the same graphs.
SPARQL 1.2 Update requests are sequences of operations.
Each request SHOULD be treated atomically by a SPARQL 1.2 Update service. The term 'atomically' means that a single request will result in either no effect or a complete effect, regardless of the number of operations that may be present in the request. Any resulting concurrency issues will be a matter for each implementation to consider according to its own architecture. In particular, using the SERVICE keyword in the WHERE clause of operations in an Update request will usually result in a loss of atomicity.
In the case of two different update services, whose respective Graph Stores contain graphs with the same names, there is no presumption that the updates done through one service will be propagated to the other, as the stores are independent entities. The behaviour of these services with respect to each other (such as automatic synchronization after updates) is implementation dependent.
If the store is capable of calculating entailed answers, see [[[SPARQL12-ENTAILMENT]]], then it is possible for update
operations to interact with entailed data. In particular, a DELETE operation may attempt to remove entailed statements without actual effects.
After an update request is completed, a store that performs consistency checking with respect to a particular entailment regime on its graphs MAY check the new state of the Graph Store for consistency. If inconsistency is detected, such a store MAY return an error to the request.
Also of note is that some stores may be capable of performing entailments with respect to an ontology capable of higher level processing, such as RDFS or OWL. Updates may interact with these entailment regimes in these systems.
SPARQL 1.2 Update supports two categories of update operations on a Graph Store:
A request is a sequence of operations and is terminated by EOF (End of File). Multiple operations are separated by a ';' (semicolon) character. A semicolon after the last operation in a request is optional. Implementations MUST ensure that the operations of a single request are executed in a fashion that guarantees the same effects as executing them sequentially in the order they appear in the request.
Operations all result either in success or failure. A failure result MAY be accompanied by extra information, indicating that some portion of the operations in the request were successful. This document does not stipulate the exact form of the result, as that will be dependent on the interface being used, for instance the [[[SPARQL12-PROTOCOL]]] via HTTP or a programmatic API. If multiple operations are present in a single request, then a result of failure from any operation MUST abort the sequence of operations, causing the subsequent operations to be ignored.
The formal semantics of the following operations is defined in Section 4 of this document.
Graph update operations change existing graphs in the Graph Store but do not explicitly delete nor create them. Non-empty inserts into non-existing graphs will, however, implicitly create those graphs, i.e., an implementation fulfilling an update request SHOULD silently an automatically create graphs that do not exist before triples are inserted into them, and MUST return with failure if it fails to do so for any reason. (For example, the implementation may have insufficient resources, or an implementation may only provide an update service over a fixed set of graphs and the implicitly created graph is not within this fixed set). An implementation MAY remove graphs that are left empty after triples are removed from them.
If a graph is created implicitly by an update operation, then the behavior of the Graph Store MUST be functionally equivalent to its behavior if the graph had been created explicitly by a CREATE operation.
SPARQL 1.2 Update provides these graph update operations:
INSERT DATA operation adds some triples, given inline in the request, into a graph.
This SHOULD create the destination graph if it does not exist. If the graph does not exist and it can not be created for any reason, then a failure MUST be returned.DELETE DATA operation removes some triples, given inline in the request, if the respective graph contains those.INSERT and DELETE (which can co-occur in a single DELETE/INSERT operation). These actions consist of groups of triples to be deleted and groups of triples to be added. The specification of the triples is based on
query patterns. The difference between INSERT / DELETE and INSERT DATA / DELETE DATA is that INSERT DATA and DELETE
DATA do not substitute bindings into a template from a pattern. The DATA forms require concrete data (triple templates containing variables within DELETE
DATA and INSERT DATA operations are disallowed and blank nodes are disallowed within DELETE DATA, see Notes 8+9 in the grammar). Having specific operations for concrete data means that a request can be streamed so that large, pure-data updates
can be done.LOAD operation reads the contents of a document representing a graph into a graph in the Graph Store.CLEAR operation removes all the triples in (one or more) graphs.The INSERT DATA operation adds some triples, given inline in the request, into the Graph Store:
INSERT DATA QuadData
where QuadData are formed by TriplesTemplates, i.e., sets of triple
patterns, optionally wrapped into a GRAPH block.
( GRAPH VarOrIri )? { TriplesTemplate? }
Variables in QuadDatas are disallowed in INSERT DATA requests (see Notes 8 in the grammar). That is, the INSERT DATA statement only allows to insert ground triples. Blank nodes in
QuadDatas are assumed to be disjoint from the blank nodes in the Graph Store, i.e., will be inserted with "fresh" blank nodes.
If no graph is described in the QuadData, then the default graph is presumed.
If data is inserted into a graph that does not exist in the Graph Store, it SHOULD be created (there may be implementations providing an
update service over a fixed set of graphs which in such case MUST return with failure for update requests that insert data into an unallowed graph).
Note that a triple MAY be considered to be "processed" with no action if that triple already exists in the graph. Further, note that
INSERT DATA { GRAPH <g> {} } ...
does not create <g>. If a user intends to just create a graph, then the graph management operations (CREATE/LOAD) may be used prior to any
insertion operations.
Example 1: Adding some triples to a graph
This snippet describes two RDF triples to be inserted into the default graph of the Graph Store.
PREFIX dc: <http://purl.org/dc/elements/1.1/>
INSERT DATA
{
<http://example/book1> dc:title "A new book" ;
dc:creator "A.N.Other" .
}
Data before:
# Default graph PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX ns: <http://example.org/ns#> <http://example/book1> ns:price 42 .
Data after:
# Default graph PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX ns: <http://example.org/ns#> <http://example/book1> ns:price 42 . <http://example/book1> dc:title "A new book" . <http://example/book1> dc:creator "A.N.Other" .
Example 2: Adding a triple to a named graph
This SPARQL 1.2 Update request adds a triple to provide the price of a book. In contrast to the previous example, which affected the default graph,
the requested change happens in the named graph identified by the IRI http://example/bookStore.
PREFIX dc: <http://purl.org/dc/elements/1.1/>
PREFIX ns: <http://example.org/ns#>
INSERT DATA
{ GRAPH <http://example/bookStore> { <http://example/book1> ns:price 42 } }
Data before:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book1> dc:title "Fundamentals of Compiler Design" .
Data after:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX ns: <http://example.org/ns#> <http://example/book1> dc:title "Fundamentals of Compiler Design" . <http://example/book1> ns:price 42 .
Example 3: Adding a reifying triple
When inserting triples containing reifying triples,
these reifying triples are not automatically inserted as asserted triples.
In other words, when executing the INSERT DATA operation below,
the default graph will not contain the triple :bob :age 23.
PREFIX : <http://www.example.org/>
INSERT DATA
{ :alice :claims << :bob :age 23 >> . }
Data before is the empty graph.
Data after:
PREFIX : <http://www.example.org/> :alice :claims << :bob :age 23 >> .
If a reifying triple is to be present as an asserted triple,
then it needs to be explicitly inserted, through an operation like the following INSERT DATA.
PREFIX : <http://www.example.org/>
INSERT DATA
{
:alice :claims << :bob :age 23 >>.
:bob :age 23.
}
Data after:
PREFIX : <http://www.example.org/> :alice :claims << :bob :age 23 >> . :bob :age 23 .
The DELETE DATA operation removes some triples, given inline in the request, if the respective graphs in the Graph Store contain those:
DELETE DATA QuadData
QuadData denotes triples to be removed and is as described in INSERT DATA, with the difference that in a DELETE
DATA operation neither variables nor blank nodes are allowed (see Notes 8+9 in the grammar).
As with INSERT DATA, DELETE DATA is meant for deletion of ground triples data which is why QuadData that contains variables or blank nodes
is disallowed in DELETE DATA operations. The DELETE/INSERT operation can be used to remove triples containing blank nodes.
Note that the deletion of non-existing triples has no effect, i.e., triples in the QuadData that did not exist in the Graph Store are ignored. Blank nodes are not
permitted in the QuadData, as these do not match any existing data.
Example 4: Removing triples from a graph
This request describes 2 triples to be removed from the default graph of the Graph Store.
PREFIX dc: <http://purl.org/dc/elements/1.1/>
DELETE DATA
{
<http://example/book2> dc:title "David Copperfield" ;
dc:creator "Edmund Wells" .
}
Data before:
# Default graph PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX ns: <http://example.org/ns#> <http://example/book2> ns:price 42 . <http://example/book2> dc:title "David Copperfield" . <http://example/book2> dc:creator "Edmund Wells" .
Data after:
# Default graph PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX ns: <http://example.org/ns#> <http://example/book2> ns:price 42 .
Example 5: Removing a triple from a named graph
This SPARQL 1.2 Update request consists of two operations, including a triple to be deleted and a triple to be added (used here to correct a book
title). As opposed to the previous example, which affected the default graph, the requested change happens in the named graph identified by the IRI
http://example/bookStore.
PREFIX dc: <http://purl.org/dc/elements/1.1/>
DELETE DATA
{ GRAPH <http://example/bookStore> { <http://example/book1> dc:title "Fundamentals of Compiler Desing" } } ;
PREFIX dc: <http://purl.org/dc/elements/1.1/>
INSERT DATA
{ GRAPH <http://example/bookStore> { <http://example/book1> dc:title "Fundamentals of Compiler Design" } }
Data before:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book1> dc:title "Fundamentals of Compiler Desing" .
Data after:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book1> dc:title "Fundamentals of Compiler Design" .
Example 6: Removing a reifying triple
When deleting triples containing reifying triples,
these reifying triples are not automatically deleted as asserted triples.
In other words, when executing the DELETE DATA operation below,
the default graph will still contain the triple :bob :age 23
if it was previously present as an asserted triple.
PREFIX : <http://www.example.org/>
DELETE DATA
{
:alice :claims << :bob :age 23 >>.
}
Data before:
PREFIX : <http://www.example.org/> :alice :claims << :bob :age 23 >> . :bob :age 23 .
Data after:
PREFIX : <http://www.example.org/> :bob :age 23 .
In contrast, deleting an asserted triple with the request shown below would not delete any triple containing this triple as a reifying triple.
PREFIX : <http://www.example.org/>
DELETE DATA
{
:bob :age 23 .
}
The DELETE/INSERT operation can be used to remove or add triples from/to the Graph Store based on bindings for a query pattern specified in a
WHERE clause:
( WITH IRIref )? ( ( DeleteClause InsertClause? ) | InsertClause ) ( USING ( NAMED )? IRIref )* WHERE GroupGraphPattern
The DeleteClause and InsertClause forms can be broken down as follows:
DeleteClause ::= DELETEQuadPatternInsertClause ::= INSERTQuadPattern
This operation identifies data with the WHERE clause, which will be used to compute solution sequences of bindings for a set of variables. The bindings for each solution are
then substituted into the DELETE template to remove triples, and then in the INSERT template to create new triples. If any solution produces a triple containing an
unbound variable or an illegal RDF construct, such as a literal in a subject or predicate position, then that triple is not included when processing the operation: INSERT will
not instantiate new data in the output graph, and DELETE will not remove anything. The graphs used for computing a solution sequence may be different to the graphs modified
with the DELETE and INSERT templates.
The WITH clause defines the graph that will be modified or matched against for any of the subsequent elements (in DELETE, INSERT, or
WHERE clauses) if they do not specify a graph explicitly. If not provided, then the default graph of the Graph Store (or an explicitly declared dataset in the
WHERE clause) will be assumed. That is, a WITH clause may be viewed as syntactic sugar for wrapping both the QuadPatterns in subsequent
DELETE and INSERT clauses, and likewise the GroupGraphPattern in the subsequent WHERE clause into GRAPH patterns.
This can be used to avoid refering to the same graph multiple times in a single operation.
Following the optional WITH clause are the INSERT and/or DELETE clauses. The deletion of the triples happens before the insertion. The pattern in
the WHERE clause is evaluated only once, before the delete part of the operation is performed. The overall processing model is that the pattern is executed, the results used to
instantiate the DELETE template, the deletes performed, the results used again to instantiate the INSERT template, and the inserts performed.
If the DELETE clause is omitted, then the operation only inserts data (see INSERT). If the INSERT clause is omitted, then the
operation only removes data (see DELETE). The grammar does not permit both DELETE and INSERT to be omitted in the same
operation.
The USING and
USING NAMED clauses affect the RDF Dataset used while
evaluating the WHERE clause. This describes a dataset in the same way as FROM and FROM NAMED clauses describe RDF Datasets in the SPARQL 1.2 Query Language. The keyword USING instead of FROM in update requests is
to avoid possible ambiguities which could arise from writing "DELETE FROM". That is, the GroupGraphPattern in the WHERE clause will be matched against the dataset described by
explicit USING or USING NAMED clauses, if specified, and against the Graph Store otherwise.
The WITH clause provides a convenience for when an operation primarily refers to a single graph. If a graph name is specified in a WITH clause, then — for the
purposes of evaluating the WHERE clause — this will define an RDF Dataset containing a default graph with the specified name, but only in the absence of USING or
USING NAMED clauses. In the presence of one or more graphs referred to in USING clauses and/or USING NAMED clauses, the WITH clause will
be ignored while evaluating the WHERE clause.
The GroupGraphPattern in the WHERE clause is evaluated as in a SPARQL query
"SELECT * WHERE GroupGraphPattern" and all the solution bindings are applied to the preceding DELETE and INSERT templates for defining the
triples to be deleted from or inserted into the Graph Store.
Again, QuadPatterns are formed by TriplesTemplates, i.e., sets of triple
patterns, optionally wrapped into a GRAPH block, where the GRAPH clause indicates the named graph in the Graph Store to be updated; on any
TripleTemplates without a GRAPH clause, the INSERT or DELETE clauses applies to the graph specified by the WITH
clause, or the default graph of the Graph Store if no WITH clause is present.
To illustrate the use of the WITH clause, an operation of the general form:
WITH <g1> DELETE { a b c } INSERT { x y z } WHERE { ... }
is considered equivalent to:
DELETE { GRAPH <g1> { a b c } } INSERT { GRAPH <g1> { x y z } } USING <g1> WHERE { ... }
Note that explicit GRAPH clauses override a WITH clause. WITH provides a fallback to specify a graph (different from the default graph) to use when
one is not explicitly stipulated via GRAPH.
Deleting triples that are not present, or from a graph that is not present will have no effect and will result in success. Blank nodes are prohibited in a DELETE
template, since using a new blank node in a DELETE template would lead to nothing being deleted, as a new blank node cannot match anything in the Graph Store. It should be
noted that this restriction is not in the EBNF for the DeleteClause itself, but made explicit in Note
9 to the grammar.
If an operation tries to insert into a graph that does not exist, then that graph SHOULD be created; again, there may be implementations providing an update service over a fixed set of graphs which in such case MUST return with failure for update requests that would create an unallowed graph. If no data is to be inserted, then no graph will be created. Particularly, note that
INSERT ... { GRAPH <g> {} } ...
does not create <g>. If a user intends to create a graph regardless of the data to be inserted, then the graph management operations (CREATE/LOAD) may be used prior to any insertion operations.
Blank nodes that appear in an INSERT clause operate similarly to blank nodes in the template of a CONSTRUCT query, i.e., they are re-instantiated for any
solution of the WHERE clause; refer to Templates with Blank Nodes in SPARQL Query 1.2 and to the formal semantics of DELETE/INSERT below for details. Blank nodes in the WHERE clause match data in the same way as for any SPARQL Query.
Example 7: Updating a named graph
An example to update the graph http://example/addresses to rename all people with the given name "Bill" to "William".
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
WITH <http://example/addresses>
DELETE { ?person foaf:givenName 'Bill' }
INSERT { ?person foaf:givenName 'William' }
WHERE
{ ?person foaf:givenName 'Bill'
}
Data before:
# Graph: http://example/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/president25> foaf:givenName "Bill" . <http://example/president25> foaf:familyName "McKinley" . <http://example/president27> foaf:givenName "Bill" . <http://example/president27> foaf:familyName "Taft" . <http://example/president42> foaf:givenName "Bill" . <http://example/president42> foaf:familyName "Clinton" .
Data after:
# Graph: http://example/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/president25> foaf:givenName "William" . <http://example/president25> foaf:familyName "McKinley" . <http://example/president27> foaf:givenName "William" . <http://example/president27> foaf:familyName "Taft" . <http://example/president42> foaf:givenName "William" . <http://example/president42> foaf:familyName "Clinton" .
Example 8: Updating reifying triples
Just like with the INSERT DATA and DELETE DATA operations,
inserting or deleting triples containing reifying triples does not automatically
impact asserted triples.
It is still possible to impact such triples by explicitly asserting them, as shown below.
PREFIX : <http://www.example.org/>
DELETE { :alice ?pp << ?s ?p ?o >> . }
INSERT { :carol ?pp << ?s ?p ?o >> . ?s ?p ?o .}
WHERE { :alice ?pp << ?s ?p ?o >> . }
( WITH IRIref )?
DELETE QuadPattern
( USING ( NAMED )? IRIref )*
WHERE GroupGraphPattern
The DELETE operation is a form of the DELETE/INSERT operation having no INSERT section. A compliant implementation of
DELETE/INSERT will already implement this operation correctly. The DELETE operation is described here separately for clarity. Analogous to DELETE/INSERT, deleting triples that are not present, or from a graph that is not present will have no effect and will result in success.
If any DELETE template specifies a GRAPH then this will be the graph affected. Otherwise, the operation will be applied to the graph specified in the
WITH clause, if one was specified, or the default graph otherwise.
The WHERE clause identifies data in existing graphs, and creates bindings to be used by the template. The graphs to apply the GroupGraphPattern follow the same
rules as for DELETE/INSERT.
Example 9:
This example request deletes all records of old books (with date before year 1970) from the store's default graph:
PREFIX dc: <http://purl.org/dc/elements/1.1/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
DELETE
{ ?book ?p ?v }
WHERE
{ ?book dc:date ?date .
FILTER ( ?date < "1970-01-01T00:00:00-02:00"^^xsd:dateTime )
?book ?p ?v
}
The pattern in WHERE is matched against the Graph Store. The resulting sequence of solutions to the WHERE clause is used to instantiate the triple patterns in the
DELETE template similar to CONSTRUCT in SPARQL 1.2 Query. The resulting triples are then removed from the Graph Store.
Data before:
# Default graph PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book1> dc:title "Principles of Compiler Design" . <http://example/book1> dc:date "1977-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book2> ns:price 42 . <http://example/book2> dc:title "David Copperfield" . <http://example/book2> dc:creator "Edmund Wells" . <http://example/book2> dc:date "1948-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book3> dc:title "SPARQL 1.2 Tutorial" .
Data after:
# Default graph PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book2> ns:price 42 . <http://example/book2> dc:title "David Copperfield" . <http://example/book2> dc:creator "Edmund Wells" . <http://example/book2> dc:date "1948-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book3> dc:title "SPARQL 1.2 Tutorial" .
Example 10:
This example request removes all statements about anything with a given name of "Fred" from the graph http://example/addresses. A
WITH clause is present, meaning that graph http://example/addresses is both the one from which triples are being removed and the one which the WHERE
clause is matched against.
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
WITH <http://example/addresses>
DELETE { ?person ?property ?value }
WHERE { ?person ?property ?value ; foaf:givenName 'Fred' }
Data before:
# Graph: http://example/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> . <http://example/fred> a foaf:Person . <http://example/fred> foaf:givenName "Fred" . <http://example/fred> foaf:mbox <mailto:fred@example> .
Data after:
# Graph: http://example/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
Another example of DELETE is provided in the final example in the following section which demonstrates multiple operations combining an
INSERT with a DELETE.
( WITH IRIref )?
INSERT QuadPattern
( USING ( NAMED )? IRIref )*
WHERE GroupGraphPattern
The INSERT operation is a form of the DELETE/INSERT operation having no DELETE section. A compliant implementation of
DELETE/INSERT will already implement this operation correctly. The INSERT operation is described here separately for clarity.
If the INSERT template specifies GRAPH blocks then these will be the graphs affected. Otherwise, the operation will be applied to the default graph, or,
respectively, to the graph specified in the WITH clause, if one was specified. If no USING (NAMED) clause is present, then the pattern in the WHERE
clause will be matched against the Graph Store, otherwise against the dataset specified by the USING (NAMED) clauses. The matches against the WHERE clause create
bindings to be applied to the template for determining triples to be inserted (following the same rules as for DELETE/INSERT).
If any instantiation arising from the solution sequence produces a triple containing an unbound variable or an illegal RDF construct, such as a literal in subject or predicate position, then that triple is not inserted. The template can contain triples with no variables (known as ground or explicit triples), and these will also be inserted, provided that the solution sequence is not empty.
Example 11:
This example copies triples from one named graph to another named graph based on a pattern:
PREFIX dc: <http://purl.org/dc/elements/1.1/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
INSERT
{ GRAPH <http://example/bookStore2> { ?book ?p ?v } }
WHERE
{ GRAPH <http://example/bookStore>
{ ?book dc:date ?date .
FILTER ( ?date > "1970-01-01T00:00:00-02:00"^^xsd:dateTime )
?book ?p ?v
} }
Data before:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> <http://example/book1> dc:title "Fundamentals of Compiler Design" . <http://example/book1> dc:date "1977-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book2> ns:price 42 . <http://example/book2> dc:title "David Copperfield" . <http://example/book2> dc:creator "Edmund Wells" . <http://example/book2> dc:date "1948-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book3> dc:title "SPARQL 1.2 Tutorial" .
# Graph: http://example/bookStore2 PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book4> dc:title "SPARQL 1.0 Tutorial" .
Data after:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> <http://example/book1> dc:title "Fundamentals of Compiler Design" . <http://example/book1> dc:date "1977-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book2> ns:price 42 . <http://example/book2> dc:title "David Copperfield" . <http://example/book2> dc:creator "Edmund Wells" . <http://example/book2> dc:date "1948-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book3> dc:title "SPARQL 1.2 Tutorial" .
# Graph: http://example/bookStore2 PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> <http://example/book1> dc:title "Fundamentals of Compiler Design" . <http://example/book1> dc:date "1977-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book4> dc:title "SPARQL 1.0 Tutorial" .
Example 12:
This example copies triples of name and email from one named graph to another. Some individuals may not have an address, but the name is copied regardless:
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
INSERT
{ GRAPH <http://example/addresses>
{
?person foaf:name ?name .
?person foaf:mbox ?email
} }
WHERE
{ GRAPH <http://example/people>
{
?person foaf:name ?name .
OPTIONAL { ?person foaf:mbox ?email }
} }
Data before:
# Graph: http://example/people PREFIX foaf: <http://xmlns.com/foaf/0.1/> PREFIX rdf: >http://www.w3.org/1999/02/22-rdf-syntax-ns#> _:a rdf:type foaf:Person . _:a foaf:name "Alice" . _:a foaf:mbox <mailto:alice@example.com> . _:b rdf:type foaf:Person . _:b foaf:name "Bob" .
# Graph: http://example/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/>
Data after:
# Graph: http://example/people PREFIX foaf: <http://xmlns.com/foaf/0.1/> PREFIX rdf: >http://www.w3.org/1999/02/22-rdf-syntax-ns#> _:a rdf:type foaf:Person . _:a foaf:name "Alice" . _:a foaf:mbox <mailto:alice@example.com> . _:b rdf:type foaf:Person . _:b foaf:name "Bob" .
# Graph: http://example/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> _:a foaf:name "Alice" . _:a foaf:mbox <mailto:alice@example.com> . _:b foaf:name "Bob" .
Example 13:
This example request first copies triples from one named graph to another named graph based on a pattern; triples about all the copied objects
that are classified as Physical Objects are then deleted. This demonstrates two operations in a single request, both of which share common PREFIX definitions.
PREFIX dc: <http://purl.org/dc/elements/1.1/>
PREFIX dcmitype: <http://purl.org/dc/dcmitype/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
INSERT
{ GRAPH <http://example/bookStore2> { ?book ?p ?v } }
WHERE
{ GRAPH <http://example/bookStore>
{ ?book dc:date ?date .
FILTER ( ?date < "2000-01-01T00:00:00-02:00"^^xsd:dateTime )
?book ?p ?v
}
} ;
WITH <http://example/bookStore>
DELETE
{ ?book ?p ?v }
WHERE
{ ?book dc:date ?date ;
dc:type dcmitype:PhysicalObject .
FILTER ( ?date < "2000-01-01T00:00:00-02:00"^^xsd:dateTime )
?book ?p ?v
}
Data before:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX dcmitype: <http://purl.org/dc/dcmitype/> <http://example/book1> dc:title "Fundamentals of Compiler Design" . <http://example/book1> dc:date "1996-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book1> a dcmitype:PhysicalObject . <http://example/book3> dc:title "SPARQL 1.2 Tutorial" .
# Graph: http://example/bookStore2 PREFIX dc: <http://purl.org/dc/elements/1.1/> <http://example/book4> dc:title "SPARQL 1.0 Tutorial" .
Data after:
# Graph: http://example/bookStore PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX dcmitype: <http://purl.org/dc/dcmitype/> <http://example/book3> dc:title "SPARQL 1.2 Tutorial" .
# Graph: http://example/bookStore2 PREFIX dc: <http://purl.org/dc/elements/1.1/> PREFIX dcmitype: <http://purl.org/dc/dcmitype/> <http://example/book1> dc:title "Fundamentals of Compiler Design" . <http://example/book1> dc:date "1996-01-01T00:00:00-02:00"^^xsd:dateTime . <http://example/book1> a dcmitype:PhysicalObject . <http://example/book4> dc:title "SPARQL 1.0 Tutorial" .
DELETE WHERE QuadPattern
The DELETE WHERE operation is a shortcut form for the DELETE/INSERT operation where bindings matched by the WHERE
clause are used to define the triples in a graph that will be deleted. Analogous to DELETE/INSERT, deleting triples that are not present, or from a graph that is not present
will have no effect and will result in success.
The QuadPattern is used both as a pattern for matching against triples and graphs, and as the
template for deletion. If any TripleTemplates within the QuadPattern appear in
the scope of a GRAPH clause then this will determine the graph that that template is matched on, and also the graph from which any matching triples will be removed. Any
TripleTemplates not in the scope of a GRAPH clause will be matched against/removed from the default graph.
Example 14:
This example request removes all statements about anything with a given name of "Fred" from the default graph:
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
DELETE WHERE { ?person foaf:givenName 'Fred';
?property ?value }
Data before:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> . <http://example/fred> a foaf:Person . <http://example/fred> foaf:givenName "Fred" . <http://example/fred> foaf:mbox <mailto:fred@example> .
Data after:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
Example 15:
This example request removes both statements naming some resource "Fred" in the graph http://example.com/names, and also
statements about that resource from the graph http://example/addresses (assuming that some of the resources in the graph http://example.com/names have
corresponding triples in the graph http://example/addresses).
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
DELETE WHERE {
GRAPH <http://example.com/names> {
?person foaf:givenName 'Fred' ;
?property1 ?value1
}
GRAPH <http://example.com/addresses> {
?person ?property2 ?value2
}
}
# Graph: http://example.com/names PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/fred> a foaf:Person . <http://example/fred> foaf:givenName "Fred" .
# Graph: http://example.com/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> foaf:mbox <mailto:bill@example> . <http://example/fred> foaf:mbox <mailto:fred@example> .
Data after:
# Graph: http://example.com/names PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" .
# Graph: http://example.com/addresses PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> foaf:mbox <mailto:bill@example> .
The `LOAD` operation reads an RDF document from an IRI and inserts triples from the document into the Graph Store.
LOAD ( SILENT )? IRIref_from ( INTO GRAPH IRIref_to )?
IRIref_from specifies the IRI of a document, such that a store will be able to identify, locate, and read the document. The most common IRIs will be URLs in the `https` and `http` IRI schemes.
If a destination graph (IRIref_to) is specified by `INTO GRAPH`, then the specified destination graph SHOULD be created if required; again, implementations providing an update service over a fixed set of graphs MUST return with failure for a request that would create a disallowed graph. If the destination graph already exists, then no data in that graph will be removed. The RDF document is retrieved and parsed to produce an RDF Graph. This graph is merged into the destination graph in the graph store.
If no destination graph IRI is specified by `INTO`, then the RDF document is retrieved and parsed into an RDF Dataset. This dataset is merged into the graph store viewed as a mutable RDF Dataset.
If no RDF data can be retrieved (as opposed to an empty graph being retrieved) from the IRI denoted by IRIref_from, or in case the retrieval method returns an error (such as, for instance an HTTP error code), the SPARQL 1.2 Update service SHOULD return failure and the status of the Graph Store SHOULD remain in the same status as prior to the request. However, if the the keyword `SILENT` is present, operation will return success, rather than failure, and the status of the Graph Store is is not specified.
Some RDF syntaxes, such as [[[JSON-LD11]]], are often used to serialize a single graph with no graph name. [[[RDF12-N-QUADS]]] may be used as a database dump format for a triple store with the data only in the default graph. When the `LOAD` operation has an `INTO GRAPH` clause, it is an error if named graphs are encountered when parsing the RDF document.
The CLEAR operation removes all the triples in the specified graph(s) in the Graph Store.
CLEAR ( SILENT )? (GRAPH IRIref | DEFAULT | NAMED | ALL )
Here, the DEFAULT keyword is used to remove all triples in the default graph of the Graph Store, the NAMED keyword is used to remove all triples in all named
graphs of the Graph Store and the ALL keyword is used to remove all triples in all graphs of the Graph Store. The GRAPH keyword is used to remove all triples from
a graph denoted by IRIref. This operation is not required to remove the empty graphs from the Graph Store, but an implementation MAY decide to do so.
# Remove all triples from a specified graph. CLEAR GRAPH IRIref
in principle has the same effect as:
# Remove all triples from the graph named with the IRI denoted by IRIref.
DELETE { GRAPH IRIref { ?s ?p ?o } } WHERE { GRAPH IRIref { ?s ?p ?o } }
CLEAR DEFAULT may have further implications which we
leave unspecified here.
If the store records the existence of empty graphs, then the SPARQL 1.2 Update service, by default, SHOULD return
failure if the specified graph does not exist. If SILENT is present, the result of the operation will always be success.
Stores that do not record empty graphs will always return success.
Graph management operations allow creating, destroying, moving and copying named graphs in the Graph Store, or adding the contents of one graph to another. Operations for creation and destruction are not required to result in any actions, since Graph Stores are not required to record the existence of empty named graphs.
The default graph in a Graph Store always exists.
SPARQL 1.2 Update provides these graph management operations:
CREATE operation creates a new graph in stores that support empty graphs.DROP operation removes a graph and all of its contents.COPY operation modifies a graph to contain a copy of another.MOVE operation moves all of the data from one graph into another.ADD operation reproduces all data from one graph into another.This operation creates a graph in the Graph Store:
CREATE ( SILENT )? GRAPH IRIref
For stores that record empty graphs, this will create a new empty graph in the store with a name specified by the IRI. If the graph already exists, then a failure SHOULD be returned, except when the SILENT keyword is used; in either case, the contents of already existing graphs remain
unchanged. If the graph may not be created, then a failure MUST be returned, except when the SILENT
keyword is used.
Stores that do not record empty named graphs will always return success on creation of a non-existing graph.
DROP ( SILENT )? (GRAPH IRIref | DEFAULT | NAMED | ALL )
The DROP operation removes the specified graph(s) from the Graph Store. The GRAPH keyword is used to remove a graph denoted by IRIref, the
DEFAULT keyword is used to remove the default graph from the Graph Store, the NAMED keyword is used to remove all named graphs from the Graph Store, and the
ALL keyword is used to remove all graphs from the Graph Store, i.e., resetting the store. After successful completion of this operation, the specified graphs are no longer
available for further graph update operations. However, in case the DEFAULT graph of the Graph Store is dropped, implementations MUST restore it after it was removed, i.e., DROP DEFAULT is equivalent to CLEAR DEFAULT.
If the store records the existence of empty graphs, then the SPARQL 1.2 Update service, by default, SHOULD return
failure if the specified named graph does not exist. If SILENT is present, the result of the operation will always be success.
Stores that do not record empty graphs will always return success.
The COPY operation is a shortcut for inserting all data from an input graph into a destination graph. Data from the input graph is not affected, but data from the
destination graph, if any, is removed before insertion.
COPY ( SILENT )? ( ( GRAPH )? IRIref_from | DEFAULT) TO ( ( GRAPH )? IRIref_to | DEFAULT )
is similar in operation to:
DROP SILENT (GRAPH IRIref_to | DEFAULT);
INSERT { ( GRAPH IRIref_to )? { ?s ?p ?o } } WHERE { ( GRAPH IRIref_from )? { ?s ?p ?o } }
The difference between COPY and the DROP/INSERT combination is that if COPY is used to copy a graph onto itself then no operation will be performed
and the data will be left as it was. Using DROP/INSERT in this situation would result in an empty graph.
If the destination graph does not exist, it will be created. By default, the service MAY return failure if the input
graph does not exist. If SILENT is present, the result of the operation will always be success.
Example 16:
This example request copies all statements from the default graph to a named graph:
COPY DEFAULT TO <http://example.org/named>
Data before:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
# Graph http://example.org/named <http://example/fred> a foaf:Person . <http://example/fred> foaf:givenName "Fred" .
Data after:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
# Graph http://example.org/named PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
Note that the original content in http://example.org/named is lost by a COPY operation.
The MOVE operation is a shortcut for moving all data from an input graph into a destination graph. The input graph is removed after insertion and data from the destination
graph, if any, is removed before insertion.
MOVE (SILENT)? ( ( GRAPH )? IRIref_from | DEFAULT) TO ( ( GRAPH )? IRIref_to | DEFAULT)
is similar in operation to:
DROP SILENT (GRAPH IRIref_to | DEFAULT);
INSERT { ( GRAPH IRIref_to )? { ?s ?p ?o } } WHERE { ( GRAPH IRIref_from )? { ?s ?p ?o } };
DROP ( GRAPH IRIref_from | DEFAULT)
The difference between MOVE and the DROP/INSERT/DROP combination is that if MOVE is used to move a graph onto itself then no operation will be
performed and the data will be left as it was. Using DROP/INSERT/DROP in this situation would result in the graph being removed.
If the destination graph does not exist, it will be created. By default, the service MAY return failure if the input
graph does not exist. If SILENT is present, the result of the operation will always be success.
Example 17:
This example request moves all statements from the default graph into a named graph:
MOVE DEFAULT TO <http://example.org/named>
Data before:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
# Graph http://example.org/named PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/fred> a foaf:Person . <http://example/fred> foaf:givenName "Fred" .
Data after:
# Default graph
# Graph http://example.org/named PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
Note that the original content in http://example.org/named is lost by a MOVE operation.
The ADD operation is a shortcut for inserting all data from an input graph into a destination graph. Data from the input graph is not affected, and initial data from the
destination graph, if any, is kept intact.
ADD ( SILENT )? ( ( GRAPH )? IRIref_from | DEFAULT) TO ( ( GRAPH )? IRIref_to | DEFAULT)
is equivalent to:
INSERT { ( GRAPH IRIref_to )? { ?s ?p ?o } } WHERE { ( GRAPH IRIref_from )? { ?s ?p ?o } }
If the destination graph does not exist, it will be created. By default, the service MAY return failure if the input
graph does not exist. If SILENT is present, the result of the operation will always be success.
Example 18:
This example request adds all statements from the default graph to a named graph:
ADD DEFAULT TO <http://example.org/named>
Data before:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
# Graph http://example.org/named PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/fred> a foaf:Person .
Data after:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
# Graph http://example.org/named PREFIX foaf: <http://xmlns.com/foaf/0.1/> <http://example/fred> a foaf:Person . <http://example/william> a foaf:Person . <http://example/william> foaf:givenName "William" . <http://example/william> foaf:mbox <mailto:bill@example> .
This section formally defines the semantics of Update Operations by describing their effects in terms of transformations of the Graph Store.
Definition: Graph Store
A Graph Store GS is a mutable container of RDF graphs. It has one unnamed (default) slot and zero or more named slots. The unnamed slot holds an RDF graph; each named slot is a pair of a graph and an associated IRI. The Graph Store can be viewed as a mutable RDF Dataset.
GS = {DG, (iri1, G1), ..., (irin, Gn) }
where
Definition: Update Operation
An Update Operation Op is an atomic operation that accepts some arguments Args and transforms a Graph Store GS to another Graph Store GS', denoted as
Op(GS, Args) = GS'
By 'atomic operation' we mean that the operation performs the described transformation of the Graph Store either completely or leaves the Graph Store unchanged, i.e., the result is either GS' or GS (in case of error).
An Update Operation can create new slots and new RDF graphs, or can remove existing slots and the corresponding graphs. It can also alter the state of each slot individually.
We will define the semantics of each concrete update operation in terms of concrete instances of this abstract update operation definition.
In the following we present auxiliary functions and basic operations for creating the union, and difference of RDF Datasets. The concrete update operations will be defined in terms of those basic operations.
This basic operation creates the union of two RDF Datasets.
Definition: Dataset-UNION
Let DS={DG} union {(irii, Gi) | 1 ≤ i ≤ n} and DS' = {DG'} union {(iri'j, G'j) | 1 ≤ j ≤ m} be two RDF Datasets. Let further graphNames(DS) = { irii | 1 ≤ i ≤ n} and graphNames(DS') = {iri'j | 1 ≤ j ≤ m}. The Dataset-UNION between DS and DS' is defined as follows:
Dataset-UNION(DS, DS') = {DG union DG'} union {(iri, G) | iri in graphNames(DS) union graphNames(DS')}
and G defined as
where union between graphs is defined as set-union of triples in those graphs.
This operation removes the triples of a given dataset from another dataset.
Definition: Dataset-DIFF
Let DS={DG} union {(irii, Gi) | 1 ≤ i ≤ n} and DS' = {DG'} union {(iri'j, G'j) | 1 ≤ j ≤ m}) be two RDF Datasets. Let further graphNames(DS) = { irii | 1 ≤ i ≤ n} and graphNames(DS') = {iri'j | 1 ≤ j ≤ m}. The Dataset-DIFF between DS and DS' is defined as follows:
Dataset-DIFF(DS, DS') = {DG minus DG'} union { (iri, G) | iri in graphNames(DS) })
and G defined as
where Gi minus G'j is defined as set-difference over the sets of triples in the two graphs.
QuadPattern, μ, DS, GS )The following auxiliary function constructs an RDF Dataset from a QuadPattern, given a solution mapping and
an RDF Dataset.
Let μ be a solution mapping, DS={DG} union {(irii, Gi) | 1 ≤ i ≤ n} be an RDF Dataset and GS be
the current state of the Graph Store. DS is distinguished from GS as they may differ, for instance, due to the use of USING [NAMED] to modify DS.
For a QuadPattern of the form
'{}'
Dataset ( QuadPattern, μ, DS, GS ) = {{}}, i.e., the empty dataset consisting only of an empty default graph.
'{' TriplesTemplate? '}'
Dataset ( QuadPattern, μ, DS, GS ) is the Dataset consisting of only a default graph composed by all valid RDF
triples obtained from substituting the variables in skμ(TriplesTemplate) according to μ
and combining these triples into a single RDF graph by set union.
'GRAPH' VarOrIri '{' TriplesTemplate? '}'
Dataset ( QuadPattern, μ, DS, GS ) is the Dataset consisting of an empty default graph, plus — in case μ(VarOrIri) yields a valid IRI — a named graph (μ(VarOrIri), G) such that G is composed by all valid RDF triples obtained from substituting the variables
in skμ(TriplesTemplate) according to μ and combining these triples into a single RDF graph
by set union.
'{' QuadPattern1 QuadPattern2 '}'
Dataset ( QuadPattern, μ, DS, GS ) = Dataset-UNION ( Dataset ( QuadPattern1, μ, DS, GS ), Dataset ( QuadPattern2, μ, DS, GS ) )
Here, skμ(TriplesTemplate) stands for replacing any blank nodes occurring in the
TriplesTemplate with a new, unique blank node (unique to the current update request and to each μ and
different from any blank nodes used in DS or in GS).
The function skμ guarantees that "fresh" blank nodes in the QuadPattern are re-instantiated "per solution" μ (analogous to the treatment of blank nodes in CONSTRUCT templates in the [[[SPARQL12-QUERY]]]); cf. also the respective remarks on scoping of blank nodes within requests in the SPARQL grammar.
QuadPattern, P, DS, GS )The following auxiliary function constructs an RDF Dataset from a QuadPattern, given a graph pattern and an
RDF Dataset.
Let P be a Graph Pattern and DS={DG} union {(irii, Gi) | 1 ≤ i ≤ n} be an RDF Dataset and GS be the current state of the Graph Store. Then
Dataset ( QuadPattern, P, DS, GS ) = Dataset-UNION ( { Dataset ( QuadPattern, μ, DS, GS ) | μ in eval'( DS ( DG ), P ) } )
i.e., the union over all μ such that μ is in the solutions of P over dataset DS.
Here, eval'() is defined exactly like the evaluation function eval() in the [[[SPARQL12-QUERY]]], with the only exception, that here — as opposed to the treatment of blank nodes in BGP matching for SPARQL 1.2 Query — the scoping graph SG used for BGP matching is equal to the active graph, i.e., blank nodes from the active graph are preserved in solutions.
The definition of eval'() guarantees that co-referent blank nodes in DS are not "lost" during pattern evaluation, cf. Treatment of Blank Nodes in [[[SPARQL12-QUERY]]]. The latter is necessary to ensure that blank nodes in DS can be matched against existing blank nodes in GS to remove/add triples. In order to illustrate matching against existing blank nodes in the Graph Store, the following update request removes all triples with blank node as subject.
DELETE { ?S ?P ?O . } WHERE { ?S ?P ?O . FILTER ( isBlank ( ?S ) ) }
Data before:
# Default graph PREFIX : <http://example.com/> PREFIX foaf: <http://xmlns.com/foaf/0.1/> _:b a foaf:Person . :s a foaf:Person .
Data after:
# Default graph PREFIX foaf: <http://xmlns.com/foaf/0.1/> :s a foaf:Person .
Definition: Insert Data Operation
A Insert Data Operation is an Update Operation in which new triples, given as a (ground) QuadPattern, are added in the Graph Store GS, in the default slot or in named slots.
OpInsertData(GS, QuadPattern) = Dataset-UNION(GS, Dataset ( QuadPattern, {}, GS, GS ) )
where {} is the empty solution mapping.
Definition: Delete Data Operation
A Delete Data Operation OpDeleteData is an Update Operation in which triples, given as a (ground) QuadPattern, are removed from the Graph Store GS, from the default slot or from named slots.
OpDeleteData ( GS, QuadPattern) = Dataset-DIFF ( GS, Dataset ( QuadPattern, {}, GS, GS ) )
where {} is the empty solution mapping.
Definition: Delete Insert Operation
A Delete Insert Operation OpDeleteInsert is an Update Operation in which (1) triples are deleted from the Graph Store GS, either from the default slot or
from named slot(s), and then (2) new triples are added in the Graph Store GS, either in the default slot or in named slot(s). Triples to be removed (and inserted, respectively) are
identified by applying the pattern solutions for a Group Graph Pattern P against DS to the QuadPattern QuadPatternDEL (and QuadPatternINS, respectively).
OpDeleteInsert ( GS, DS, QuadPatternDEL, QuadPatternINS, P) = Dataset-UNION ( Dataset-DIFF ( GS, Dataset ( QuadPatternDEL, P, DS, GS ) ), Dataset ( QuadPatternINS, P, DS, GS )
Definition: Load Operation
A Load Operation `OpLoad` is an Update Operation in which new triples (from a remote graph or dataset) are added to the Graph Store, either in the default slot or in a named slot, if specified.
OpLoad ( GS, documentIRI) = dataset-merge ( GS, dataset ( documentIRI ) } )
OpLoad ( GS, documentIRI, iri ) = dataset-merge(GS, { {}, ( iri, graph ( documentIRI ) ) } )
where
dataset ( documentIRI ) is a function
returning the RDF dataset serialized by the RDF documentgraph ( documentIRI ) is a function
returning the RDF graph serialized by the RDF documentBlank nodes present in the retrieved graph or dataset are "standardized apart"; i.e., blank nodes from a loaded graph or dataset are disjoint from the blank nodes already present in the Graph Store GS.
Definition: Clear Operation
A Clear Operation OpClear is an Update Operation in which triples are deleted from the Graph Store, either from a named slot, the default slot, all named slots or all slots. There are different variants of the Clear Operation, OpClear for clearing a named graph, OpCleardef for clearing the default graph, OpClearnamed for clearing all named graphs, and OpClearall for clearing all graphs including the default graph.
Let GS = {DG} union {(irii, Gi) | 1 ≤ i ≤ n} and graphNames(GS) = { irii | 1 ≤ i ≤ n}, then
OpClear(GS, iri) = GS if iri not in graphNames(GS); otherwise, OpClear(GS, irij) = ( GS minus {(irij, Gj)} ) union {(irij,{})}, where (irij, Gj) ∈ GS and iri = irij
OpCleardef(GS) = {{}} union {(irii, Gi) | 1 ≤ i ≤ n}
OpClearnamed(GS) = {DG} union {(irii, {}) | 1 ≤ i ≤ n}
OpClearall(GS) = {{}} union {(irii, {}) | 1 ≤ i ≤ n}
Definition: Create Operation
A Create Operation OpCreate is an Update Operation in which (1) a new named slot and (2) a new graph G are created in the Graph Store. The new graph is held in the new slot, and is empty. Other slots and graphs are not affected.
Let GS = {DG} union {(irii, Gi) | 1 ≤ i ≤ n} and graphNames(GS) = { irii | 1 ≤ i ≤ n}, then
OpCreate(GS, iri) = GS union {(iri, {})} if iri not in graphNames(GS); otherwise, OpCreate(GS, iri) = GS
Definition: Drop Operation
A Drop Operation OpDrop is an Update Operation in which one or more slots (a named slot irii, the default slot, all named slots or all slots) and their corresponding graphs are removed from the Graph Store. There are different variants of the Drop Operation, OpDrop for dropping a named graph, OpDropdef for dropping the default graph (which is equivalent to OpCleardef, since the default graph cannot be removed, but dropping it means only to clear it), OpDropnamed for dropping all named graphs, and OpDropall for dropping all graphs including the default graph.
Let GS = {DG} union {(irii, Gi) | 1 ≤ i ≤ n} and graphNames(GS) = { irii | 1 ≤ i ≤ n}, then
OpDrop(GS, iri) = GS if iri not in graphNames(GS); otherwise, OpDrop(GS, irij) = {DG} union {(irii, Gi ) | i ≠ j and 1 ≤ i ≤ n} where iri = irij
OpDropdef(GS) = OpCleardef(GS)
OpDropnamed(GS) = {DG}
OpDropall(GS) = {{}}
In this section we show how to map Update Requests in the SPARQL 1.2. Update Language to Update Operations over the Graph Store as defined earlier in this section. This mapping assumes
that in all Update requests, any PREFIXes have been expanded. Moreover, we assume that WITH clauses have been replaced by wrapping both the
QuadPatterns in subsequent DELETE and INSERT clauses, and likewise — in the absence of USING and USING NAMED clauses
— the GroupGraphPattern in the subsequent WHERE clause, into GRAPH patterns.
The mapping from requests to Update Operations is defined in terms of the recursive translation function Tr(GS,R) which takes the Graphstore GS — as before executing the
request — and an update request R as input and exands it to an Update Operation call as shown in the following table. The COPY, MOVE, and ADD operations are not mentioned explicitly here, since they are understood as
shortcuts.
| Update request R | Tr(GS,R) = |
|---|---|
| R1 ; R2 | Tr(Tr(GS, R1), R2) |
INSERT DATA QuadData |
OpInsertData(GS, QuadData) |
DELETE DATA QuadData |
OpDeleteData(GS, QuadData) |
DELETE QuadPatternDEL INSERT QuadPatternINSUsingClause* WHERE GroupGraphPattern |
OpDeleteInsert(GS, TrDataset(GS,UsingClause*), QuadPatternDEL, QuadPatternINS, GroupGraphPattern) |
DELETE QuadPatternDELUsingClause* WHERE GroupGraphPattern |
OpDeleteInsert(GS, TrDataset(GS,UsingClause*), QuadPatternDEL, {}, GroupGraphPattern) |
INSERT QuadPatternINSUsingClause* WHERE GroupGraphPattern |
OpDeleteInsert(GS, TrDataset(GS,UsingClause*), {}, QuadPatternINS, GroupGraphPattern) |
DELETE WHERE QuadPattern |
OpDeleteInsert(GS, GS, QuadPattern, {}, QuadPattern) |
LOAD (SILENT)? IRIref |
OpLoad(GS, IRIref) |
LOAD (SILENT)? IRIreffrom INTO GRAPH IRIrefto |
OpLoad(GS, IRIreffrom, IRIrefto) |
CLEAR (SILENT)? GRAPH IRIref |
OpClear(GS, IRIref) |
CLEAR (SILENT)? DEFAULT |
OpCleardef(GS) |
CLEAR (SILENT)? NAMED |
OpClearnamed(GS) |
CLEAR (SILENT)? ALL |
OpClearall(GS) |
CREATE (SILENT)? GRAPH IRIref |
OpCreate(GS, IRIref) |
DROP (SILENT)? GRAPH IRIref |
OpDrop(GS, IRIref) |
DROP (SILENT)? DEFAULT |
OpDropdef(GS) |
DROP (SILENT)? NAMED |
OpDropnamed(GS) |
DROP (SILENT)? ALL |
OpDropall(GS) |
This table uses one auxiliary translation function TrDataset() which constructs a dataset from the optional set of USING and USING NAMED
clauses and is defined as follows:
| Translation Function | Definition |
|---|---|
| TrDataset(GS,UsingClause*) = |
|
USING and USING NAMED clauses (e.g., by dereferencing graph name IRIs
and trying to retrieve them, or by picking those graphs from the existing Graph Store) is implementation dependent. Particularly, this specification does not mandate any assumptions about
blank node identity beyond the consideration for the analogous FROM and FROM NAMED clauses in Section Specifying RDF Datasets of the SPARQL 1.2 Query Language specification.
See appendix B SPARQL 1.2 Update Grammar regarding conformance of SPARQL Update strings.
This specification is intended for use in conjunction with: the [[[SPARQL12-GRAPH-STORE-PROTOCOL]]] and the [[[SPARQL12-PROTOCOL]]].
Exposing RDF data for update creates many security issues which all deployments must be aware of, and consider the risks involved. This submission discusses some of the potential issues. New security problems are discovered regularly, and each implementation introduces its own concerns. Consequently implementers should be aware that this is only a partial list containing possible issues, and cannot be considered complete nor authoritative.
The Internet Media Type (formerly known as MIME Type) for the SPARQL Update Language is "application/sparql-update".
It is recommended that SPARQL Update files have the extension ".ru" (lowercase) on all platforms.
It is recommended that SPARQL Update files stored on Macintosh HFS file systems be given a file type of "TEXT".
The formal definition for the SPARQL 1.2 Update grammar is provided with the SPARQL 1.2 Query grammar. This is because the grammar for SPARQL 1.2 Update shares most of its structure with SPARQL 1.2 Query.
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