Class: SPARQL::Algebra::Operator::DeleteData

Inherits:
Unary show all
Includes:
Update
Defined in:
lib/sparql/algebra/operator/delete_data.rb

Overview

The SPARQL UPDATE deleteData operator.

The DELETE DATA operation removes some triples, given inline in the request, if the respective graphs in the Graph Store contain those

[39] DeleteData ::= ‘DELETE DATA’ QuadData

Examples:

SPARQL Grammar

PREFIX     : <http://example.org/> 
PREFIX foaf: <http://xmlns.com/foaf/0.1/> 
DELETE DATA {
  :a foaf:knows :b .
}

SSE

(prefix ((: <http://example.org/>) (foaf: <http://xmlns.com/foaf/0.1/>))
 (update (deleteData ((triple :a foaf:knows :b)))))

See Also:

Constant Summary collapse

NAME = 
[:deleteData]

Constants inherited from Unary

Unary::ARITY

Constants inherited from SPARQL::Algebra::Operator

ARITY, IsURI, URI

Constants included from Expression

Expression::PATTERN_PARENTS

Instance Attribute Summary

Attributes inherited from SPARQL::Algebra::Operator

#operands

Instance Method Summary collapse

Methods included from Update

#graph_name=, #unshift, #variables

Methods inherited from Unary

#initialize

Methods inherited from SPARQL::Algebra::Operator

#aggregate?, arity, #base_uri, base_uri, base_uri=, #bind, #boolean, #constant?, #deep_dup, #each_descendant, #eql?, #evaluatable?, evaluate, #executable?, #first_ancestor, for, #initialize, #inspect, #ndvars, #node?, #operand, #optimize, #optimize!, #parent, #parent=, #prefixes, prefixes, prefixes=, #rewrite, #to_binary, to_sparql, #to_sxp, #to_sxp_bin, #validate!, #variable?, #variables, #vars

Methods included from Expression

cast, #constant?, #evaluate, extension, extension?, extensions, for, #invalid?, new, #node?, open, #optimize, #optimize!, parse, register_extension, #to_sxp_bin, #valid?, #validate!, #variable?

Constructor Details

This class inherits a constructor from SPARQL::Algebra::Operator::Unary

Instance Method Details

#execute(queryable, **options) ⇒ RDF::Queryable

Executes this upate on the given writable graph or repository.

Parameters:

  • queryable (RDF::Queryable) —

    the graph or repository to write

  • options (Hash{Symbol => Object}) —

    any additional keyword options

Options Hash (**options):

  • debug (Boolean) —

    Query execution debugging

Returns:

Raises:

  • (IOError) —

    If from does not exist, unless the silent operator is present

See Also:



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# File 'lib/sparql/algebra/operator/delete_data.rb', line 42

def execute(queryable, **options)
  operand.each do |op|
    debug(options) {"DeleteData #{op.to_sxp}"}
    queryable.delete(op)
  end
  queryable
end

#to_sparql(**options) ⇒ String

Returns a partial SPARQL grammar for this term.

Returns:

  • (String) 


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# File 'lib/sparql/algebra/operator/delete_data.rb', line 55

def to_sparql(**options)
  "DELETE DATA {\n" +
    operands.first.to_sparql(top_level: false, delimiter: ". \n", **options) +
    "\n}"
end