1/* Part of SWI-Prolog 2 3 Author: Jan Wielemaker 4 E-mail: J.Wielemaker@vu.nl 5 WWW: http://www.swi-prolog.org 6 Copyright (c) 2003-2023, University of Amsterdam 7 VU University Amsterdam 8 CWI, Amsterdam 9 SWI-Prolog Solutions b.v. 10 All rights reserved. 11 12 Redistribution and use in source and binary forms, with or without 13 modification, are permitted provided that the following conditions 14 are met: 15 16 1. Redistributions of source code must retain the above copyright 17 notice, this list of conditions and the following disclaimer. 18 19 2. Redistributions in binary form must reproduce the above copyright 20 notice, this list of conditions and the following disclaimer in 21 the documentation and/or other materials provided with the 22 distribution. 23 24 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 26 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 27 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 28 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 29 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 30 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 31 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 32 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 34 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 POSSIBILITY OF SUCH DAMAGE. 36*/ 37 38:- module(rdf_db, 39 [ rdf_version/1, % -Version 40 41 rdf/3, % ?Subject, ?Predicate, ?Object 42 rdf/4, % ?Subject, ?Predicate, ?Object, ?DB 43 rdf_has/3, % ?Subject, +Pred, ?Obj 44 rdf_has/4, % ?Subject, +Pred, ?Obj, -RealPred 45 rdf_reachable/3, % ?Subject, +Pred, ?Object 46 rdf_reachable/5, % ?Subject, +Pred, ?Object, +MaxD, ?D 47 rdf_resource/1, % ?Resource 48 rdf_subject/1, % ?Subject 49 50 rdf_member_property/2, % ?Property, ?Index 51 52 rdf_assert/3, % +Subject, +Predicate, +Object 53 rdf_assert/4, % +Subject, +Predicate, +Object, +DB 54 rdf_retractall/3, % ?Subject, ?Predicate, ?Object 55 rdf_retractall/4, % ?Subject, ?Predicate, ?Object, +DB 56 rdf_update/4, % +Subject, +Predicate, +Object, +Act 57 rdf_update/5, % +Subject, +Predicate, +Object, +Src, +Act 58 rdf_set_predicate/2, % +Predicate, +Property 59 rdf_predicate_property/2, % +Predicate, ?Property 60 rdf_current_predicate/1, % -Predicate 61 rdf_current_literal/1, % -Literal 62 rdf_transaction/1, % :Goal 63 rdf_transaction/2, % :Goal, +Id 64 rdf_transaction/3, % :Goal, +Id, +Options 65 rdf_active_transaction/1, % ?Id 66 67 rdf_monitor/2, % :Goal, +Options 68 69 rdf_save_db/1, % +File 70 rdf_save_db/2, % +File, +DB 71 rdf_load_db/1, % +File 72 rdf_reset_db/0, 73 74 rdf_node/1, % -Id 75 rdf_bnode/1, % -Id 76 rdf_is_bnode/1, % +Id 77 78 rdf_is_resource/1, % +Term 79 rdf_is_literal/1, % +Term 80 rdf_literal_value/2, % +Term, -Value 81 82 rdf_load/1, % +File 83 rdf_load/2, % +File, +Options 84 rdf_save/1, % +File 85 rdf_save/2, % +File, +Options 86 rdf_unload/1, % +File 87 rdf_unload_graph/1, % +Graph 88 89 rdf_md5/2, % +DB, -MD5 90 rdf_atom_md5/3, % +Text, +Times, -MD5 91 92 rdf_create_graph/1, % ?Graph 93 rdf_graph_property/2, % ?Graph, ?Property 94 rdf_set_graph/2, % +Graph, +Property 95 rdf_graph/1, % ?Graph 96 rdf_source/1, % ?File 97 rdf_source/2, % ?DB, ?SourceURL 98 rdf_make/0, % Reload modified databases 99 rdf_gc/0, % Garbage collection 100 101 rdf_source_location/2, % +Subject, -Source 102 rdf_statistics/1, % -Key 103 rdf_set/1, % +Term 104 rdf_generation/1, % -Generation 105 rdf_snapshot/1, % -Snapshot 106 rdf_delete_snapshot/1, % +Snapshot 107 rdf_current_snapshot/1, % +Snapshot 108 rdf_estimate_complexity/4, % +S,+P,+O,-Count 109 110 rdf_save_subject/3, % +Stream, +Subject, +DB 111 rdf_save_header/2, % +Out, +Options 112 rdf_save_footer/1, % +Out 113 114 rdf_equal/2, % ?Resource, ?Resource 115 lang_equal/2, % +Lang1, +Lang2 116 lang_matches/2, % +Lang, +Pattern 117 118 rdf_prefix/2, % :Alias, +URI 119 rdf_current_prefix/2, % :Alias, ?URI 120 rdf_register_prefix/2, % +Alias, +URI 121 rdf_register_prefix/3, % +Alias, +URI, +Options 122 rdf_unregister_prefix/1, % +Alias 123 rdf_current_ns/2, % :Alias, ?URI 124 rdf_register_ns/2, % +Alias, +URI 125 rdf_register_ns/3, % +Alias, +URI, +Options 126 rdf_global_id/2, % ?NS:Name, :Global 127 rdf_global_object/2, % +Object, :NSExpandedObject 128 rdf_global_term/2, % +Term, :WithExpandedNS 129 130 rdf_compare/3, % -Dif, +Object1, +Object2 131 rdf_match_label/3, % +How, +String, +Label 132 rdf_split_url/3, % ?Base, ?Local, ?URL 133 rdf_url_namespace/2, % +URL, ?Base 134 135 rdf_warm_indexes/0, 136 rdf_warm_indexes/1, % +Indexed 137 rdf_update_duplicates/0, 138 139 rdf_debug/1, % Set verbosity 140 141 rdf_new_literal_map/1, % -Handle 142 rdf_destroy_literal_map/1, % +Handle 143 rdf_reset_literal_map/1, % +Handle 144 rdf_insert_literal_map/3, % +Handle, +Key, +Literal 145 rdf_insert_literal_map/4, % +Handle, +Key, +Literal, -NewKeys 146 rdf_delete_literal_map/3, % +Handle, +Key, +Literal 147 rdf_delete_literal_map/2, % +Handle, +Key 148 rdf_find_literal_map/3, % +Handle, +KeyList, -Literals 149 rdf_keys_in_literal_map/3, % +Handle, +Spec, -Keys 150 rdf_statistics_literal_map/2, % +Handle, +Name(-Arg...) 151 152 rdf_graph_prefixes/2, % ?Graph, -Prefixes 153 rdf_graph_prefixes/3, % ?Graph, -Prefixes, :Filter 154 155 (rdf_meta)/1, % +Heads 156 op(1150, fx, (rdf_meta)) 157 ]). 158:- use_module(library(semweb/rdf_prefixes), 159 [ (rdf_meta)/1, 160 register_file_prefixes/1, 161 rdf_global_id/2, 162 rdf_register_ns/2, 163 % re-exported predicates 164 rdf_global_object/2, 165 rdf_current_ns/2, 166 rdf_prefix/2, 167 rdf_global_term/2, 168 rdf_register_ns/3, 169 rdf_register_prefix/3, 170 rdf_register_prefix/2, 171 rdf_current_prefix/2, 172 rdf_unregister_prefix/1 173 ]). 174 175:- autoload(library(apply),[maplist/2,maplist/3]). 176:- use_module(library(debug),[debug/3,assertion/1]). 177:- autoload(library(error),[must_be/2,existence_error/2]). 178:- autoload(library(gensym),[gensym/2,reset_gensym/1]). 179:- autoload(library(lists), 180 [member/2,flatten/2,list_to_set/2,append/3,select/3]). 181:- autoload(library(memfile), 182 [atom_to_memory_file/2,open_memory_file/4]). 183:- autoload(library(option), 184 [option/2,option/3,merge_options/3,meta_options/3]). 185:- autoload(library(rdf),[process_rdf/3]). 186:- autoload(library(sgml), 187 [ load_structure/3, 188 xml_quote_attribute/3, 189 xml_name/1, 190 xml_quote_cdata/3, 191 xml_is_dom/1, 192 iri_xml_namespace/3, 193 iri_xml_namespace/2 194 ]). 195:- autoload(library(sgml_write),[xml_write/3]). 196:- autoload(library(uri), 197 [ uri_file_name/2, 198 uri_is_global/1, 199 uri_normalized/2, 200 uri_components/2, 201 uri_data/3, 202 uri_data/4 203 ]). 204:- autoload(library(xsdp_types),[xsdp_numeric_uri/2]). 205:- autoload(library(semweb/rdf_cache),[rdf_cache_file/3]). 206 207:- if(exists_source(library(thread))). 208:- autoload(library(thread), [concurrent/3]). 209:- endif. 210 211:- use_foreign_library(foreign(rdf_db)). 212:- public rdf_print_predicate_cloud/2. % print matrix of reachable predicates 213 214:- meta_predicate 215 rdf_transaction(), 216 rdf_transaction(, ), 217 rdf_transaction(, , ), 218 rdf_monitor(, ), 219 rdf_save(, ), 220 rdf_load(, ). 221 222:- predicate_options(rdf_graph_prefixes/3, 3, 223 [ expand(callable+4), 224 filter(callable+3), 225 get_prefix(callable+2), 226 min_count(nonneg) 227 ]). 228:- predicate_options(rdf_load/2, 2, 229 [ base_uri(atom), 230 blank_nodes(oneof([share,noshare])), 231 cache(boolean), 232 concurrent(positive_integer), 233 db(atom), 234 format(oneof([xml,triples,turtle,trig,nquads,ntriples])), 235 graph(atom), 236 multifile(boolean), 237 if(oneof([true,changed,not_loaded])), 238 modified(-float), 239 prefixes(-list), 240 silent(boolean), 241 register_namespaces(boolean) 242 ]). 243:- predicate_options(rdf_save/2, 2, 244 [ graph(atom), 245 db(atom), 246 anon(boolean), 247 base_uri(atom), 248 write_xml_base(boolean), 249 convert_typed_literal(callable), 250 encoding(encoding), 251 document_language(atom), 252 namespaces(list(atom)), 253 xml_attributes(boolean), 254 inline(boolean) 255 ]). 256:- predicate_options(rdf_save_header/2, 2, 257 [ graph(atom), 258 db(atom), 259 namespaces(list(atom)) 260 ]). 261:- predicate_options(rdf_save_subject/3, 3, 262 [ graph(atom), 263 base_uri(atom), 264 convert_typed_literal(callable), 265 document_language(atom) 266 ]). 267:- predicate_options(rdf_transaction/3, 3, 268 [ snapshot(any) 269 ]). 270 271:- discontiguous 272 term_expansion/2.
288 /******************************* 289 * PREFIXES * 290 *******************************/ 291 292% the ns/2 predicate is historically defined in this module. We'll keep 293% that for compatibility reasons. 294 295:- multifile ns/2. 296:- dynamic ns/2. % ID, URL 297 298:- multifile 299 rdf_prefixes:rdf_empty_prefix_cache/2. 300 301rdf_prefixesrdf_empty_prefix_cache(_Prefix, _IRI) :- 302 rdf_empty_prefix_cache. 303 304:- rdf_meta 305 rdf(r,r,o), 306 rdf_has(r,r,o,r), 307 rdf_has(r,r,o), 308 rdf_assert(r,r,o), 309 rdf_retractall(r,r,o), 310 rdf(r,r,o,?), 311 rdf_assert(r,r,o,+), 312 rdf_retractall(r,r,o,?), 313 rdf_reachable(r,r,o), 314 rdf_reachable(r,r,o,+,?), 315 rdf_update(r,r,o,t), 316 rdf_update(r,r,o,+,t), 317 rdf_equal(o,o), 318 rdf_source_location(r,-), 319 rdf_resource(r), 320 rdf_subject(r), 321 rdf_create_graph(r), 322 rdf_graph(r), 323 rdf_graph_property(r,?), 324 rdf_set_graph(r,+), 325 rdf_unload_graph(r), 326 rdf_set_predicate(r, t), 327 rdf_predicate_property(r, -), 328 rdf_estimate_complexity(r,r,r,-), 329 rdf_print_predicate_cloud(r,+).
335rdf_equal(Resource, Resource).343lang_equal(Lang, Lang) :- !. 344lang_equal(Lang1, Lang2) :- 345 downcase_atom(Lang1, LangCannon), 346 downcase_atom(Lang2, LangCannon).
358 /******************************* 359 * BASIC TRIPLE QUERIES * 360 *******************************/
literal(Value) if the
object is a literal value. If a value of the form
NameSpaceID:LocalName is provided it is expanded to a ground
atom using expand_goal/2. This implies you can use this
construct in compiled code without paying a performance penalty.
Literal values take one of the following forms:
rdf:datatype
TypeID. The Value is either the textual representation or a
natural Prolog representation. See the option
convert_typed_literal(:Convertor) of the parser. The storage
layer provides efficient handling of atoms, integers (64-bit)
and floats (native C-doubles). All other data is represented
as a Prolog record.
For literal querying purposes, Object can be of the form
literal(+Query, -Value), where Query is one of the terms below.
If the Query takes a literal argument and the value has a
numeric type numerical comparison is performed.
icase(Text). Backward compatibility.
Backtracking never returns duplicate triples. Duplicates can be
retrieved using rdf/4. The predicate rdf/3 raises a type-error
if called with improper arguments. If rdf/3 is called with a
term literal(_) as Subject or Predicate object it fails
silently. This allows for graph matching goals like
rdf(S,P,O),rdf(O,P2,O2) to proceed without errors.
rdf(Subject, Predicate, Object) is true
exploiting the rdfs:subPropertyOf predicate as well as inverse
predicates declared using rdf_set_predicate/2 with the
inverse_of property.inverse_of(Pred).symetric(true) or inverse_of(P2) properties.
If used with either Subject or Object unbound, it first returns the origin, followed by the reachable nodes in breadth-first search-order. The implementation internally looks one solution ahead and succeeds deterministically on the last solution. This predicate never generates the same node twice and is robust against cycles in the transitive relation.
With all arguments instantiated, it succeeds deterministically if a path can be found from Subject to Object. Searching starts at Subject, assuming the branching factor is normally lower. A call with both Subject and Object unbound raises an instantiation error. The following example generates all subclasses of rdfs:Resource:
?- rdf_reachable(X, rdfs:subClassOf, rdfs:'Resource'). X = 'http://www.w3.org/2000/01/rdf-schema#Resource' ; X = 'http://www.w3.org/2000/01/rdf-schema#Class' ; X = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#Property' ; ...
infinite to impose no
distance-limit.
526rdf_subject(Resource) :-
527 rdf_resource(Resource),
528 ( rdf(Resource, _, _) -> true ).This predicate is primarily intended as a way to process all resources without processing resources twice. The user must be aware that some of the returned resources may not appear in any visible triple.
541 /******************************* 542 * TRIPLE MODIFICATIONS * 543 *******************************/
user. Subject and Predicate are
resources. Object is either a resource or a term literal(Value).
See rdf/3 for an explanation of Value for typed and language
qualified literals. All arguments are subject to name-space
expansion. Complete duplicates (including the same graph and
`line' and with a compatible `lifespan') are not added to the
database.literal(Value).595 /******************************* 596 * COLLECTIONS * 597 *******************************/
603term_expansion(member_prefix(x), 604 member_prefix(Prefix)) :- 605 rdf_db:ns(rdf, NS), 606 atom_concat(NS, '_', Prefix). 607member_prefix(x). 608 609rdf_member_property(P, N) :- 610 integer(N), 611 !, 612 member_prefix(Prefix), 613 atom_concat(Prefix, N, P). 614rdf_member_property(P, N) :- 615 member_prefix(Prefix), 616 atom_concat(Prefix, Sub, P), 617 atom_number(Sub, N). 618 619 620 /******************************* 621 * ANONYMOUS SUBJECTS * 622 *******************************/
630rdf_node(Resource) :-
631 rdf_bnode(Resource).637rdf_bnode(Value) :- 638 repeat, 639 gensym('_:genid', Value), 640 \+ rdf(Value, _, _), 641 \+ rdf(_, _, Value), 642 \+ rdf(_, Value, _), 643 !. 644 645 646 647 /******************************* 648 * TYPES * 649 *******************************/
_:. For backward compatibility reason, __ is also
considered to be a blank node.
668rdf_is_resource(Term) :-
669 atom(Term).676rdf_is_literal(literal(Value)) :- 677 ground(Value). 678 679 /******************************* 680 * LITERALS * 681 *******************************/
| Plain literals | Atom |
| Language tagged literal | Atom holding plain text |
| xsd:string | Atom |
| rdf:XMLLiteral | XML DOM Tree |
| Numeric XSD type | Number |
706:- rdf_meta 707 rdf_literal_value(o, -), 708 typed_value(r, +, -), 709 numeric_value(r, +, -). 710 711rdf_literal_value(literal(String), Value) :- 712 atom(String), 713 !, 714 Value = String. 715rdf_literal_value(literal(lang(_Lang, String)), String). 716rdf_literal_value(literal(type(Type, String)), Value) :- 717 typed_value(Type, String, Value). 718 719typed_value(Numeric, String, Value) :- 720 xsdp_numeric_uri(Numeric, NumType), 721 !, 722 numeric_value(NumType, String, Value). 723typed_value(xsd:string, String, String). 724typed_value(rdf:'XMLLiteral', Value, DOM) :- 725 ( atom(Value) 726 -> setup_call_cleanup( 727 ( atom_to_memory_file(Value, MF), 728 open_memory_file(MF, read, In, [free_on_close(true)]) 729 ), 730 load_structure(stream(In), DOM, [dialect(xml)]), 731 close(In)) 732 ; DOM = Value 733 ). 734 735numeric_value(xsd:integer, String, Value) :- 736 atom_number(String, Value), 737 integer(Value). 738numeric_value(xsd:float, String, Value) :- 739 atom_number(String, Number), 740 Value is float(Number). 741numeric_value(xsd:double, String, Value) :- 742 atom_number(String, Number), 743 Value is float(Number). 744numeric_value(xsd:decimal, String, Value) :- 745 atom_number(String, Value). 746 747 748 /******************************* 749 * SOURCE * 750 *******************************/
758rdf_source_location(Subject, Source) :- 759 findall(Source, rdf(Subject, _, _, Source), Sources), 760 sort(Sources, Unique), 761 member(Source, Unique). 762 763 764 /******************************* 765 * GARBAGE COLLECT * 766 *******************************/
772:- public 773 rdf_create_gc_thread/0. 774 775rdf_create_gc_thread :- 776 thread_create(rdf_gc_loop, _, 777 [ alias('__rdf_GC') 778 ]).
785rdf_gc_loop :- 786 catch(rdf_gc_loop(0), E, recover_gc(E, Cont)), 787 ( Cont == true 788 -> rdf_gc_loop 789 ; thread_self(Me), 790 thread_detach(Me) 791 ). 792 793recover_gc('$aborted', false) :- 794 !. 795recover_gc(unwind(_), false) :- 796 !. 797recover_gc(Error, true) :- 798 print_message(error, Error). 799 800rdf_gc_loop(CPU) :- 801 repeat, 802 ( consider_gc(CPU) 803 -> rdf_gc(CPU1), 804 sleep(CPU1) 805 ; sleep(0.1) 806 ), 807 fail.
815rdf_gc(CPU) :-
816 statistics(cputime, CPU0),
817 ( rdf_gc_
818 -> statistics(cputime, CPU1),
819 CPU is CPU1-CPU0,
820 rdf_add_gc_time(CPU)
821 ; CPU = 0.0
822 ).__rdf_GC performs garbage collection as long as
it is considered `useful'.
Using rdf_gc/0 should only be needed to ensure a fully clean database for analysis purposes such as leak detection.
834rdf_gc :- 835 has_garbage, 836 !, 837 rdf_gc(_), 838 rdf_gc. 839rdf_gc.
845has_garbage :- 846 rdf_gc_info_(Info), 847 has_garbage(Info), 848 !. 849 850has_garbage(Info) :- arg(2, Info, Garbage), Garbage > 0. 851has_garbage(Info) :- arg(3, Info, Reindexed), Reindexed > 0. 852has_garbage(Info) :- arg(4, Info, Optimizable), Optimizable > 0.
859consider_gc(_CPU) :- 860 ( rdf_gc_info_(gc_info(Triples, % Total #triples in DB 861 Garbage, % Garbage triples in DB 862 Reindexed, % Reindexed & not reclaimed 863 Optimizable, % Non-optimized tables 864 _KeepGen, % Oldest active generation 865 _LastGCGen, % Oldest active gen at last GC 866 _ReindexGen, 867 _LastGCReindexGen)) 868 -> ( (Garbage+Reindexed) * 5 > Triples 869 ; Optimizable > 4 870 ) 871 ; print_message(error, rdf(invalid_gc_info)), 872 sleep(10) 873 ), 874 !. 875 876 877 /******************************* 878 * STATISTICS * 879 *******************************/
triples for the interpretation of this value.925rdf_statistics(graphs(Count)) :- 926 rdf_statistics_(graphs(Count)). 927rdf_statistics(triples(Count)) :- 928 rdf_statistics_(triples(Count)). 929rdf_statistics(duplicates(Count)) :- 930 rdf_statistics_(duplicates(Count)). 931rdf_statistics(lingering(Count)) :- 932 rdf_statistics_(lingering(Count)). 933rdf_statistics(resources(Count)) :- 934 rdf_statistics_(resources(Count)). 935rdf_statistics(properties(Count)) :- 936 rdf_statistics_(predicates(Count)). 937rdf_statistics(literals(Count)) :- 938 rdf_statistics_(literals(Count)). 939rdf_statistics(gc(Count, Reclaimed, Reindexed, Time)) :- 940 rdf_statistics_(gc(Count, Reclaimed, Reindexed, Time)). 941rdf_statistics(searched_nodes(Count)) :- 942 rdf_statistics_(searched_nodes(Count)). 943rdf_statistics(lookup(Index, Count)) :- 944 functor(Indexed, indexed, 16), 945 rdf_statistics_(Indexed), 946 index(Index, I), 947 Arg is I + 1, 948 arg(Arg, Indexed, Count), 949 Count \== 0. 950rdf_statistics(hash_quality(Index, Size, Quality,Optimize)) :- 951 rdf_statistics_(hash_quality(List)), 952 member(hash(Place,Size,Quality,Optimize), List), 953 index(Index, Place). 954rdf_statistics(triples_by_graph(Graph, Count)) :- 955 rdf_graph_(Graph, Count). 956 957index(rdf(-,-,-,-), 0). 958index(rdf(+,-,-,-), 1). 959index(rdf(-,+,-,-), 2). 960index(rdf(+,+,-,-), 3). 961index(rdf(-,-,+,-), 4). 962index(rdf(+,-,+,-), 5). 963index(rdf(-,+,+,-), 6). 964index(rdf(+,+,+,-), 7). 965 966index(rdf(-,-,-,+), 8). 967index(rdf(+,-,-,+), 9). 968index(rdf(-,+,-,+), 10). 969index(rdf(+,+,-,+), 11). 970index(rdf(-,-,+,+), 12). 971index(rdf(+,-,+,+), 13). 972index(rdf(-,+,+,+), 14). 973index(rdf(+,+,+,+), 15). 974 975 976 /******************************* 977 * PREDICATES * 978 *******************************/
Note that resources that have rdf:type rdf:Property are
not automatically included in the result-set of this predicate,
while all resources that appear as the second argument of a
triple are included.
994rdf_current_predicate(P, DB) :-
995 rdf_current_predicate(P),
996 ( rdf(_,P,_,DB)
997 -> true
998 ).inverse_of(Self).rdf_subject_branch_factor
property, uniqueness of the object value is computed from the
hash key rather than the actual values.rdf_subject_branch_factor, but also considering
triples of `subPropertyOf' this relation. See also rdf_has/3.rdf_object_branch_factor, but also considering
triples of `subPropertyOf' this relation. See also rdf_has/3.1051rdf_predicate_property(P, Prop) :- 1052 var(P), 1053 !, 1054 rdf_current_predicate(P), 1055 rdf_predicate_property_(P, Prop). 1056rdf_predicate_property(P, Prop) :- 1057 rdf_predicate_property_(P, Prop).
symmetric(true) is the same as inverse_of(Predicate),
i.e., creating a predicate that is the inverse of
itself.inverse_of([]).
The transitive property is currently not used. The symmetric
and inverse_of properties are considered by rdf_has/3,4 and
rdf_reachable/3.
1082 /******************************* 1083 * SNAPSHOTS * 1084 *******************************/
snapshot option. A
snapshot created outside a transaction exists until it is
deleted. Snapshots taken inside a transaction can only be used
inside this transaction.1107rdf_current_snapshot(Term) :- 1108 current_blob(Term, rdf_snapshot). 1109 1110 1111 /******************************* 1112 * TRANSACTION * 1113 *******************************/
rdf_transaction(Goal, user, []). See rdf_transaction/3.rdf_transaction(Goal, Id, []). See rdf_transaction/3.Processed options are:
true, which implies that an anonymous snapshot is
created at the current state of the store. Modifications
due to executing Goal are only visible to Goal.1149rdf_transaction(Goal) :- 1150 rdf_transaction(Goal, user, []). 1151rdf_transaction(Goal, Id) :- 1152 rdf_transaction(Goal, Id, []).
1163rdf_active_transaction(Id) :-
1164 rdf_active_transactions_(List),
1165 member(Id, List).1171rdf_monitor(Goal, Options) :- 1172 monitor_mask(Options, 0xffff, Mask), 1173 rdf_monitor_(Goal, Mask). 1174 1175monitor_mask([], Mask, Mask). 1176monitor_mask([H|T], Mask0, Mask) :- 1177 update_mask(H, Mask0, Mask1), 1178 monitor_mask(T, Mask1, Mask). 1179 1180update_mask(-X, Mask0, Mask) :- 1181 !, 1182 monitor_mask(X, M), 1183 Mask is Mask0 /\ \M. 1184update_mask(+X, Mask0, Mask) :- 1185 !, 1186 monitor_mask(X, M), 1187 Mask is Mask0 \/ M. 1188update_mask(X, Mask0, Mask) :- 1189 monitor_mask(X, M), 1190 Mask is Mask0 \/ M.
1197 % C-defined broadcasts 1198monitor_mask(assert, 0x0001). 1199monitor_mask(assert(load), 0x0002). 1200monitor_mask(retract, 0x0004). 1201monitor_mask(update, 0x0008). 1202monitor_mask(new_literal, 0x0010). 1203monitor_mask(old_literal, 0x0020). 1204monitor_mask(transaction, 0x0040). 1205monitor_mask(load, 0x0080). 1206monitor_mask(create_graph, 0x0100). 1207monitor_mask(reset, 0x0200). 1208 % prolog defined broadcasts 1209monitor_mask(parse, 0x1000). 1210monitor_mask(unload, 0x1000). % FIXME: Duplicate 1211 % mask for all 1212monitor_mask(all, 0xffff). 1213 1214%rdf_broadcast(Term, MaskName) :- 1215%% monitor_mask(MaskName, Mask), 1216%% rdf_broadcast_(Term, Mask). 1217 1218 1219 /******************************* 1220 * WARM * 1221 *******************************/
1227rdf_warm_indexes :- 1228 findall(Index, rdf_index(Index), Indexes), 1229 rdf_warm_indexes(Indexes). 1230 1231rdf_index(s). 1232rdf_index(p). 1233rdf_index(o). 1234rdf_index(sp). 1235rdf_index(o). 1236rdf_index(po). 1237rdf_index(spo). 1238rdf_index(g). 1239rdf_index(sg). 1240rdf_index(pg).
1251 /******************************* 1252 * DUPLICATES * 1253 *******************************/
The duplicates marks are used to reduce the administrative load of avoiding duplicate answers. Normally, the duplicates are marked using a background thread that is started on the first query that produces a substantial amount of duplicates.
1268:- public
1269 rdf_update_duplicates_thread/0.
1275rdf_update_duplicates_thread :-
1276 thread_create(rdf_update_duplicates, _,
1277 [ detached(true),
1278 alias('__rdf_duplicate_detecter')
1279 ]).This predicate is normally executed from a background thread named =__rdf_duplicate_detecter= which is created when a query discovers that checking for duplicates becomes too expensive.
1293 /******************************* 1294 * QUICK BINARY LOAD/SAVE * 1295 *******************************/
1305:- create_prolog_flag(rdf_triple_format, 3, [type(integer)]). 1306 1307rdf_save_db(File) :- 1308 current_prolog_flag(rdf_triple_format, Version), 1309 setup_call_cleanup( 1310 open(File, write, Out, [type(binary)]), 1311 ( set_stream(Out, record_position(false)), 1312 rdf_save_db_(Out, _, Version) 1313 ), 1314 close(Out)). 1315 1316 1317rdf_save_db(File, Graph) :- 1318 current_prolog_flag(rdf_triple_format, Version), 1319 setup_call_cleanup( 1320 open(File, write, Out, [type(binary)]), 1321 ( set_stream(Out, record_position(false)), 1322 rdf_save_db_(Out, Graph, Version) 1323 ), 1324 close(Out)).
1333rdf_load_db_no_admin(File, Id, Graphs) :-
1334 open(File, read, In, [type(binary)]),
1335 set_stream(In, record_position(false)),
1336 call_cleanup(rdf_load_db_(In, Id, Graphs), close(In)).1347check_loaded_cache(DB, [DB], _Modified) :- !. 1348check_loaded_cache(DB, Graphs, _) :- 1349 print_message(warning, rdf(inconsistent_cache(DB, Graphs))).
1356rdf_load_db(File) :- 1357 uri_file_name(URL, File), 1358 rdf_load_db_no_admin(File, URL, _Graphs). 1359 1360 1361 /******************************* 1362 * LOADING RDF * 1363 *******************************/ 1364 1365:- multifile 1366 rdf_open_hook/8, 1367 rdf_open_decode/4, % +Encoding, +File, -Stream, -Cleanup 1368 rdf_load_stream/3, % +Format, +Stream, +Options 1369 rdf_file_type/2, % ?Extension, ?Format 1370 rdf_storage_encoding/2, % ?Extension, ?Encoding 1371 url_protocol/1. % ?Protocol
rdf_load(FileOrList, []). See rdf_load/2.if(changed)=.
Options provides additional processing options. Defined options are:
share (default),
equivalent blank nodes are shared in the same resource.file:// URL when loading
a file or, if the specification is a URL, its normalized
version without the optional #fragment.true, changed (default) or
not_loaded.not_modified, cached(File),
last_modified(Stamp) or unknown.false, do not use or create a cache file.true (default false), register xmlns namespace
declarations or Turtle @prefix prefixes using
rdf_register_prefix/3 if there is no conflict.true, the message reporting completion is printed using
level silent. Otherwise the level is informational. See
also print_message/2.Other options are forwarded to process_rdf/3. By default, rdf_load/2 only loads RDF/XML from files. It can be extended to load data from other formats and locations using plugins. The full set of plugins relevant to support different formats and locations is below:
:- use_module(library(semweb/turtle)). % Turtle and TriG :- use_module(library(semweb/rdf_ntriples)). :- use_module(library(semweb/rdf_zlib_plugin)). :- use_module(library(semweb/rdf_http_plugin)). :- use_module(library(http/http_ssl_plugin)).
1467:- dynamic 1468 rdf_loading/3. % Graph, Queue, Thread 1469 1470rdf_load(Spec) :- 1471 rdf_load(Spec, []). 1472 1473:- if(\+current_predicate(concurrent/3)). 1474concurrent(_, Goals, _) :- 1475 forall(member(G, Goals), call(G)). 1476:- endif. 1477 1478% Note that we kill atom garbage collection. This improves performance 1479% with about 15% loading the LUBM Univ_50 benchmark. 1480 1481rdf_load(Spec, M:Options) :- 1482 must_be(list, Options), 1483 current_prolog_flag(agc_margin, Old), 1484 setup_call_cleanup( 1485 set_prolog_flag(agc_margin, 0), 1486 rdf_load_noagc(Spec, M, Options), 1487 set_prolog_flag(agc_margin, Old)). 1488 1489rdf_load_noagc(List, M, Options) :- 1490 is_list(List), 1491 !, 1492 flatten(List, Inputs), % Compatibility: allow nested lists 1493 maplist(must_be(ground), Inputs), 1494 length(Inputs, Count), 1495 load_jobs(Count, Jobs, Options), 1496 ( Jobs =:= 1 1497 -> forall(member(Spec, Inputs), 1498 rdf_load_one(Spec, M, Options)) 1499 ; maplist(load_goal(Options, M), Inputs, Goals), 1500 concurrent(Jobs, Goals, []) 1501 ). 1502rdf_load_noagc(One, M, Options) :- 1503 must_be(ground, One), 1504 rdf_load_one(One, M, Options). 1505 1506load_goal(Options, M, Spec, rdf_load_one(Spec, M, Options)). 1507 1508load_jobs(_, Jobs, Options) :- 1509 option(concurrent(Jobs), Options), 1510 !, 1511 must_be(positive_integer, Jobs). 1512load_jobs(Count, Jobs, _) :- 1513 current_prolog_flag(cpu_count, CPUs), 1514 CPUs > 0, 1515 !, 1516 Jobs is max(1, min(CPUs, Count)). 1517load_jobs(_, 1, _). 1518 1519 1520rdf_load_one(Spec, M, Options) :- 1521 source_url(Spec, Protocol, SourceURL), 1522 load_graph(SourceURL, Graph, Options), 1523 setup_call_cleanup( 1524 with_mutex(rdf_load_file, 1525 rdf_start_load(SourceURL, Loading)), 1526 rdf_load_file(Loading, Spec, SourceURL, Protocol, 1527 Graph, M, Options), 1528 rdf_end_load(Loading)).
1545rdf_start_load(SourceURL, queue(Queue)) :- 1546 rdf_loading(SourceURL, Queue, LoadThread), 1547 \+ thread_self(LoadThread), 1548 !, 1549 debug(rdf(load), '~p is being loaded by thread ~w; waiting ...', 1550 [ SourceURL, LoadThread]). 1551rdf_start_load(SourceURL, Ref) :- 1552 thread_self(Me), 1553 message_queue_create(Queue), 1554 assertz(rdf_loading(SourceURL, Queue, Me), Ref). 1555 1556rdf_end_load(queue(_)) :- !. 1557rdf_end_load(Ref) :- 1558 clause(rdf_loading(_, Queue, _), _, Ref), 1559 erase(Ref), 1560 thread_send_message(Queue, done), 1561 message_queue_destroy(Queue). 1562 1563rdf_load_file(queue(Queue), _Spec, _SourceURL, _Protocol, _Graph, _M, _Options) :- 1564 !, 1565 catch(thread_get_message(Queue, _), _, true). 1566rdf_load_file(_Ref, _Spec, SourceURL, Protocol, Graph, M, Options) :- 1567 debug(rdf(load), 'RDF: Loading ~q into ~q', [SourceURL, Graph]), 1568 statistics(cputime, T0), 1569 rdf_open_input(SourceURL, Protocol, Graph, 1570 In, Cleanup, Modified, Format, Options), 1571 supported_format(Format, Cleanup), 1572 return_modified(Modified, Options), 1573 ( Modified == not_modified 1574 -> Action = none 1575 ; Modified = cached(CacheFile) 1576 -> do_unload(Graph), 1577 catch(rdf_load_db_no_admin(CacheFile, cache(Graph), Graphs), _, fail), 1578 check_loaded_cache(Graph, Graphs, Modified), 1579 Action = load 1580 ; option(base_uri(BaseURI), Options, Graph), 1581 ( var(BaseURI) 1582 -> BaseURI = SourceURL 1583 ; true 1584 ), 1585 once(phrase(derived_options(Options, NSList), Extra)), 1586 merge_options([ base_uri(BaseURI), 1587 graph(Graph), 1588 format(Format) 1589 | Extra 1590 ], Options, RDFOptions), 1591 ( option(multifile(true), Options) 1592 -> true 1593 ; do_unload(Graph) 1594 ), 1595 graph_modified(Modified, ModifiedStamp), 1596 rdf_set_graph_source(Graph, SourceURL, ModifiedStamp), 1597 call_cleanup(rdf_load_stream(Format, In, M:RDFOptions), 1598 Cleanup), 1599 save_cache(Graph, SourceURL, Options), 1600 register_file_prefixes(NSList), 1601 format_action(Format, Action) 1602 ), 1603 rdf_statistics_(triples(Graph, Triples)), 1604 report_loaded(Action, SourceURL, Graph, Triples, T0, Options). 1605 1606supported_format(Format, _Cleanup) :- 1607 rdf_file_type(_, Format), 1608 !. 1609supported_format(Format, Cleanup) :- 1610 call(Cleanup), 1611 existence_error(rdf_format_plugin, Format). 1612 1613format_action(triples, load) :- !. 1614format_action(_, parsed). 1615 1616save_cache(Graph, SourceURL, Options) :- 1617 option(cache(true), Options, true), 1618 rdf_cache_file(SourceURL, write, CacheFile), 1619 !, 1620 catch(save_cache(Graph, CacheFile), E, 1621 print_message(warning, E)). 1622save_cache(_, _, _). 1623 1624derived_options([], _) --> 1625 []. 1626derived_options([H|T], NSList) --> 1627 ( { H == register_namespaces(true) 1628 ; H == (register_namespaces = true) 1629 } 1630 -> [ namespaces(NSList) ] 1631 ; [] 1632 ), 1633 derived_options(T, NSList). 1634 1635graph_modified(last_modified(Stamp), Stamp). 1636graph_modified(unknown, Stamp) :- 1637 get_time(Stamp). 1638 1639return_modified(Modified, Options) :- 1640 option(modified(M0), Options), 1641 !, 1642 M0 = Modified. 1643return_modified(_, _). 1644 1645 1646 /******************************* 1647 * INPUT HANDLING * 1648 *******************************/ 1649 1650/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1651This section deals with pluggable input sources. The task of the input 1652layer is 1653 1654 * Decide on the graph-name 1655 * Decide on the source-location 1656 * Decide whether loading is needed (if-modified) 1657 * Decide on the serialization in the input 1658 1659The protocol must ensure minimal overhead, in particular for network 1660protocols. E.g. for HTTP we want to make a single call on the server and 1661use If-modified-since to verify that we need not reloading this file. 1662- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
Options processed:
graph(Graph)db(Graph)if(Condition)cache(Cache)format(Format)
1680rdf_open_input(SourceURL, Protocol, Graph,
1681 Stream, Cleanup, Modified, Format, Options) :-
1682 ( option(multifile(true), Options)
1683 -> true
1684 ; option(if(If), Options, changed),
1685 ( If == true
1686 -> true
1687 ; rdf_graph_source_(Graph, SourceURL, HaveModified)
1688 -> true
1689 ; option(cache(true), Options, true),
1690 rdf_cache_file(SourceURL, read, CacheFile)
1691 -> time_file(CacheFile, HaveModified)
1692 ; true
1693 )
1694 ),
1695 option(format(Format), Options, _),
1696 open_input_if_modified(Protocol, SourceURL, HaveModified,
1697 Stream, Cleanup, Modified0, Format, Options),
1698 ( Modified0 == not_modified
1699 -> ( nonvar(CacheFile)
1700 -> Modified = cached(CacheFile)
1701 ; Modified = not_modified
1702 )
1703 ; Modified = Modified0
1704 ).stream(Stream)http)1715source_url(stream(In), stream(In), SourceURL) :- 1716 !, 1717 ( stream_property(In, file_name(File)) 1718 -> to_url(File, SourceURL) 1719 ; gensym('stream://', SourceURL) 1720 ). 1721source_url(Stream, Class, SourceURL) :- 1722 is_stream(Stream), 1723 !, 1724 source_url(stream(Stream), Class, SourceURL). 1725source_url(Spec, Protocol, SourceURL) :- 1726 compound(Spec), 1727 !, 1728 source_file(Spec, Protocol, SourceURL). 1729source_url(FileURL, Protocol, SourceURL) :- % or return FileURL? 1730 uri_file_name(FileURL, File), 1731 !, 1732 source_file(File, Protocol, SourceURL). 1733source_url(SourceURL0, Protocol, SourceURL) :- 1734 is_url(SourceURL0, Protocol, SourceURL), 1735 !. 1736source_url(File, Protocol, SourceURL) :- 1737 source_file(File, Protocol, SourceURL). 1738 1739source_file(Spec, file(SExt), SourceURL) :- 1740 findall(Ext, valid_extension(Ext), Exts), 1741 absolute_file_name(Spec, File, [access(read), extensions([''|Exts])]), 1742 storage_extension(_Plain, SExt, File), 1743 uri_file_name(SourceURL, File). 1744 1745to_url(URL, URL) :- 1746 uri_is_global(URL), 1747 !. 1748to_url(File, URL) :- 1749 absolute_file_name(File, Path), 1750 uri_file_name(URL, Path). 1751 1752storage_extension(Plain, SExt, File) :- 1753 file_name_extension(Plain, SExt, File), 1754 SExt \== '', 1755 rdf_storage_encoding(SExt, _), 1756 !. 1757storage_extension(File, '', File).
graph(Graph) optiondb(Graph) option (backward compatibility)base_uri(BaseURI) option1769load_graph(_Source, Graph, Options) :- 1770 option(multifile(true), Options), 1771 !, 1772 ( ( option(graph(Graph), Options) 1773 -> true 1774 ; option(db(Graph), Options) 1775 ), 1776 ground(Graph) 1777 -> true 1778 ; throw(error(existence_error(option, graph), 1779 context(_, "rdf_load/2: using multifile requires graph"))) 1780 ). 1781load_graph(Source, Graph, Options) :- 1782 ( option(graph(Graph), Options) 1783 ; option(db(Graph), Options) 1784 ), 1785 !, 1786 load_graph2(Source, Graph, Options). 1787load_graph(Source, Graph, Options) :- 1788 load_graph2(Source, Graph, Options). 1789 1790load_graph2(_, Graph, _) :- 1791 ground(Graph), 1792 !. 1793load_graph2(_Source, Graph, Options) :- 1794 option(base_uri(Graph), Options), 1795 Graph \== [], 1796 ground(Graph), 1797 !. 1798load_graph2(Source, Graph, _) :- 1799 load_graph(Source, Graph). 1800 1801load_graph(SourceURL, BaseURI) :- 1802 file_name_extension(BaseURI, Ext, SourceURL), 1803 rdf_storage_encoding(Ext, _), 1804 !. 1805load_graph(SourceURL, SourceURL). 1806 1807 1808open_input_if_modified(stream(In), SourceURL, _, In, true, 1809 unknown, Format, _) :- 1810 !, 1811 ( var(Format) 1812 -> guess_format(SourceURL, Format) 1813 ; true 1814 ). 1815open_input_if_modified(file(SExt), SourceURL, HaveModified, Stream, Cleanup, 1816 Modified, Format, _) :- 1817 !, 1818 uri_file_name(SourceURL, File), 1819 ( SExt == '' -> Plain = File; file_name_extension(Plain, SExt, File)), 1820 time_file(File, LastModified), 1821 ( nonvar(HaveModified), 1822 HaveModified >= LastModified 1823 -> Modified = not_modified, 1824 Cleanup = true 1825 ; storage_open(SExt, File, Stream, Cleanup), 1826 Modified = last_modified(LastModified), 1827 ( var(Format) 1828 -> guess_format(Plain, Format) 1829 ; true 1830 ) 1831 ). 1832open_input_if_modified(file, SourceURL, HaveModified, Stream, Cleanup, 1833 Modified, Format, Options) :- 1834 !, 1835 open_input_if_modified(file(''), SourceURL, HaveModified, 1836 Stream, Cleanup, 1837 Modified, Format, Options). 1838open_input_if_modified(Protocol, SourceURL, HaveModified, Stream, Cleanup, 1839 Modified, Format, Options) :- 1840 rdf_open_hook(Protocol, SourceURL, HaveModified, Stream, Cleanup, 1841 Modified, Format, Options). 1842 1843guess_format(File, Format) :- 1844 file_name_extension(_, Ext, File), 1845 ( rdf_file_type(Ext, Format) 1846 -> true 1847 ; Format = xml, 1848 print_message(warning, rdf(guess_format(Ext))) 1849 ).
1857storage_open('', File, Stream, close(Stream)) :- 1858 !, 1859 open(File, read, Stream, [type(binary)]). 1860storage_open(Ext, File, Stream, Cleanup) :- 1861 rdf_storage_encoding(Ext, Encoding), 1862 rdf_open_decode(Encoding, File, Stream, Cleanup). 1863 1864valid_extension(Ext) :- 1865 rdf_file_type(Ext, _). 1866valid_extension(Ext) :- 1867 rdf_storage_encoding(Ext, _).
1877is_url(URL, Scheme, FetchURL) :- 1878 atom(URL), 1879 uri_is_global(URL), 1880 uri_normalized(URL, URL1), % case normalization 1881 uri_components(URL1, Components), 1882 uri_data(scheme, Components, Scheme0), 1883 url_protocol(Scheme0), 1884 !, 1885 Scheme = Scheme0, 1886 uri_data(fragment, Components, _, Components1), 1887 uri_components(FetchURL, Components1). 1888 1889url_protocol(file). % built-in
1897rdf_file_type(xml, xml). 1898rdf_file_type(rdf, xml). 1899rdf_file_type(rdfs, xml). 1900rdf_file_type(owl, xml). 1901rdf_file_type(htm, xhtml). 1902rdf_file_type(html, xhtml). 1903rdf_file_type(xhtml, xhtml). 1904rdf_file_type(trp, triples).
1911rdf_storage_encoding('', plain).1920rdf_load_stream(xml, Stream, Options) :- 1921 !, 1922 graph(Options, Graph), 1923 rdf_transaction(load_stream(Stream, Options), 1924 parse(Graph)). 1925rdf_load_stream(xhtml, Stream, M:Options) :- 1926 !, 1927 graph(Options, Graph), 1928 rdf_transaction(load_stream(Stream, M:[embedded(true)|Options]), 1929 parse(Graph)). 1930rdf_load_stream(triples, Stream, Options) :- 1931 !, 1932 graph(Options, Graph), 1933 rdf_load_db_(Stream, Graph, _Graphs). 1934 1935load_stream(Stream, M:Options) :- 1936 process_rdf(Stream, assert_triples, M:Options), 1937 option(graph(Graph), Options), 1938 rdf_graph_clear_modified_(Graph).
1943report_loaded(none, _, _, _, _, _) :- !. 1944report_loaded(Action, Source, DB, Triples, T0, Options) :- 1945 statistics(cputime, T1), 1946 Time is T1 - T0, 1947 ( option(silent(true), Options) 1948 -> Level = silent 1949 ; Level = informational 1950 ), 1951 print_message(Level, 1952 rdf(loaded(Action, Source, DB, Triples, Time))).
1965rdf_unload(Spec) :- 1966 source_url(Spec, _Protocol, SourceURL), 1967 rdf_graph_source_(Graph, SourceURL, _), 1968 !, 1969 rdf_unload_graph(Graph). 1970rdf_unload(Graph) :- 1971 atom(Graph), 1972 rdf_graph(Graph), 1973 !, 1974 warn_deprecated_unload(Graph), 1975 rdf_unload_graph(Graph). 1976rdf_unload(_). 1977 1978:- dynamic 1979 warned/0. 1980 1981warn_deprecated_unload(_) :- 1982 warned, 1983 !. 1984warn_deprecated_unload(Graph) :- 1985 assertz(warned), 1986 print_message(warning, rdf(deprecated(rdf_unload(Graph)))).
1994rdf_unload_graph(Graph) :- 1995 must_be(atom, Graph), 1996 ( rdf_graph(Graph) 1997 -> rdf_transaction(do_unload(Graph), unload(Graph)) 1998 ; true 1999 ). 2000 2001do_unload(Graph) :- 2002 ( rdf_graph_(Graph, Triples), 2003 Triples > 0 2004 -> rdf_retractall(_,_,_,Graph) 2005 ; true 2006 ), 2007 rdf_destroy_graph(Graph). 2008 2009 /******************************* 2010 * GRAPH QUERIES * 2011 *******************************/
2023rdf_graph(Graph) :-
2024 rdf_graph_(Graph, _Triples).
2032rdf_source(Graph, SourceURL) :-
2033 rdf_graph(Graph),
2034 rdf_graph_source_(Graph, SourceURL, _Modified).
2042rdf_source(SourceURL) :-
2043 rdf_source(_Graph, SourceURL).2050rdf_make :- 2051 findall(Source-Graph, modified_graph(Source, Graph), Modified), 2052 forall(member(Source-Graph, Modified), 2053 catch(rdf_load(Source, [graph(Graph), if(changed)]), E, 2054 print_message(error, E))). 2055 2056modified_graph(SourceURL, Graph) :- 2057 rdf_graph(Graph), 2058 rdf_graph_source_(Graph, SourceURL, Modified), 2059 \+ sub_atom(SourceURL, 0, _, _, 'stream://'), 2060 Modified > 0.
modified(false).Additional graph properties can be added by defining rules for the multifile predicate property_of_graph/2. Currently, the following extensions are defined:
true if the graph is persistent.2088rdf_graph_property(Graph, Property) :- 2089 rdf_graph(Graph), 2090 property_of_graph(Property, Graph). 2091 2092:- multifile 2093 property_of_graph/2. 2094 2095property_of_graph(hash(Hash), Graph) :- 2096 rdf_md5(Graph, Hash). 2097property_of_graph(modified(Boolean), Graph) :- 2098 rdf_graph_modified_(Graph, Boolean, _). 2099property_of_graph(source(URL), Graph) :- 2100 rdf_graph_source_(Graph, URL, _). 2101property_of_graph(source_last_modified(Time), Graph) :- 2102 rdf_graph_source_(Graph, _, Time), 2103 Time > 0.0. 2104property_of_graph(triples(Count), Graph) :- 2105 rdf_graph_(Graph, Count).
2114rdf_set_graph(Graph, modified(Modified)) :-
2115 must_be(oneof([false]), Modified),
2116 rdf_graph_clear_modified_(Graph).
2123save_cache(DB, Cache) :-
2124 current_prolog_flag(rdf_triple_format, Version),
2125 setup_call_cleanup(
2126 catch(open(Cache, write, CacheStream, [type(binary)]), _, fail),
2127 rdf_save_db_(CacheStream, DB, Version),
2128 close(CacheStream)).2136assert_triples([], _). 2137assert_triples([rdf(S,P,O)|T], DB) :- 2138 !, 2139 rdf_assert(S, P, O, DB), 2140 assert_triples(T, DB). 2141assert_triples([H|_], _) :- 2142 throw(error(type_error(rdf_triple, H), _)). 2143 2144 2145 /******************************* 2146 * RESET * 2147 *******************************/
2160rdf_reset_db :- 2161 reset_gensym('_:genid'), 2162 rdf_reset_db_. 2163 2164 2165 /******************************* 2166 * SAVE RDF * 2167 *******************************/
rdf_save(Out, []). See rdf_save/2 for details.false (default true) do not save blank nodes that do
not appear (indirectly) as object of a named resource.write_xml_base option.xml:lang saved with rdf:RDF element.true (default false), inline resources when
encountered for the first time. Normally, only bnodes
are handled this way.true (default false), emit subjects sorted on
the full URI. Useful to make file comparison easier.false, do not include the xml:base
declaration that is written normally when using the
base_uri option.false (default true), never use xml attributes to
save plain literal attributes, i.e., always used an XML
element as in <name>Joe</name>.2229:- thread_local 2230 named_anon/2, % +Resource, -Id 2231 inlined/1. % +Resource 2232 2233rdf_save(File) :- 2234 rdf_save2(File, []). 2235 2236rdf_save(Spec, M:Options0) :- 2237 is_list(Options0), 2238 !, 2239 meta_options(save_meta_option, M:Options0, Options), 2240 to_file(Spec, File), 2241 rdf_save2(File, Options). 2242rdf_save(Spec, _:DB) :- 2243 atom(DB), % backward compatibility 2244 !, 2245 to_file(Spec, File), 2246 rdf_save2(File, [graph(DB)]). 2247 2248save_meta_option(convert_typed_literal). 2249 2250to_file(URL, File) :- 2251 atom(URL), 2252 uri_file_name(URL, File), 2253 !. 2254to_file(File, File). 2255 2256rdf_save2(File, Options) :- 2257 option(encoding(Encoding), Options, utf8), 2258 valid_encoding(Encoding), 2259 open_output(File, Encoding, Out, Close), 2260 flag(rdf_db_saved_subjects, OSavedSubjects, 0), 2261 flag(rdf_db_saved_triples, OSavedTriples, 0), 2262 call_cleanup(rdf_do_save(Out, Options), 2263 Reason, 2264 cleanup_save(Reason, 2265 File, 2266 OSavedSubjects, 2267 OSavedTriples, 2268 Close)). 2269 2270open_output(stream(Out), Encoding, Out, Cleanup) :- 2271 !, 2272 stream_property(Out, encoding(Old)), 2273 ( ( Old == Encoding 2274 ; Old == wchar_t % Internal encoding 2275 ) 2276 -> Cleanup = true 2277 ; set_stream(Out, encoding(Encoding)), 2278 Cleanup = set_stream(Out, encoding(Old)) 2279 ). 2280open_output(File, Encoding, Out, 2281 close(Out)) :- 2282 open(File, write, Out, [encoding(Encoding)]). 2283 2284valid_encoding(Enc) :- 2285 ( xml_encoding_name(Enc, _) 2286 -> true 2287 ; throw(error(domain_error(encoding, Enc), _)) 2288 ). 2289 2290 2291cleanup_save(Reason, 2292 File, 2293 OSavedSubjects, 2294 OSavedTriples, 2295 Close) :- 2296 call(Close), 2297 flag(rdf_db_saved_subjects, SavedSubjects, OSavedSubjects), 2298 flag(rdf_db_saved_triples, SavedTriples, OSavedTriples), 2299 retractall(named_anon(_, _)), 2300 retractall(inlined(_)), 2301 ( Reason == exit 2302 -> print_message(informational, 2303 rdf(saved(File, SavedSubjects, SavedTriples))) 2304 ; format(user_error, 'Reason = ~w~n', [Reason]) 2305 ). 2306 2307rdf_do_save(Out, Options0) :- 2308 rdf_save_header(Out, Options0, Options), 2309 graph(Options, DB), 2310 ( option(sorted(true), Options, false) 2311 -> ( var(DB) 2312 -> setof(Subject, rdf_subject(Subject), Subjects) 2313 ; findall(Subject, rdf(Subject, _, _, DB:_), SubjectList), 2314 sort(SubjectList, Subjects) 2315 ), 2316 forall(member(Subject, Subjects), 2317 rdf_save_non_anon_subject(Out, Subject, Options)) 2318 ; forall(rdf_subject_in_graph(Subject, DB), 2319 rdf_save_non_anon_subject(Out, Subject, Options)) 2320 ), 2321 rdf_save_footer(Out), 2322 !. % dubious cut; without the 2323 % cleanup handlers isn't called!?
2334rdf_subject_in_graph(Subject, DB) :- 2335 var(DB), 2336 !, 2337 rdf_subject(Subject). 2338rdf_subject_in_graph(Subject, DB) :- 2339 rdf_statistics(triples(AllTriples)), 2340 rdf_graph_property(DB, triples(DBTriples)), 2341 DBTriples > AllTriples // 10, 2342 !, 2343 rdf_resource(Subject), 2344 ( rdf(Subject, _, _, DB:_) 2345 -> true 2346 ). 2347rdf_subject_in_graph(Subject, DB) :- 2348 findall(Subject, rdf(Subject, _, _, DB:_), SubjectList), 2349 list_to_set(SubjectList, Subjects), 2350 member(Subject, Subjects). 2351 2352 2353graph(Options0, DB) :- 2354 strip_module(Options0, _, Options), 2355 ( memberchk(graph(DB0), Options) 2356 -> DB = DB0 2357 ; memberchk(db(DB0), Options) 2358 -> DB = DB0 2359 ; true % leave unbound 2360 ).
Save an RDF header, with the XML header, DOCTYPE, ENTITY and opening the rdf:RDF element with appropriate namespace declarations. It uses the primitives from section 3.5 to generate the required namespaces and desired short-name. Options is one of:
rdf and rdfs
are added to the provided List. If a namespace is not
declared, the resource is emitted in non-abreviated form.2385rdf_save_header(Out, Options) :- 2386 rdf_save_header(Out, Options, _). 2387 2388rdf_save_header(Out, Options, OptionsOut) :- 2389 is_list(Options), 2390 !, 2391 option(encoding(Enc), Options, utf8), 2392 xml_encoding(Enc, Encoding), 2393 format(Out, '<?xml version=\'1.0\' encoding=\'~w\'?>~n', [Encoding]), 2394 format(Out, '<!DOCTYPE rdf:RDF [', []), 2395 header_namespaces(Options, NSIdList), 2396 nsmap(NSIdList, NsMap), 2397 append(Options, [nsmap(NsMap)], OptionsOut), 2398 forall(member(Id=URI, NsMap), 2399 ( xml_quote_attribute(URI, NSText0, Enc), 2400 xml_escape_parameter_entity(NSText0, NSText), 2401 format(Out, '~N <!ENTITY ~w \'~w\'>', [Id, NSText]) 2402 )), 2403 format(Out, '~N]>~n~n', []), 2404 format(Out, '<rdf:RDF', []), 2405 ( member(Id, NSIdList), 2406 format(Out, '~N xmlns:~w="&~w;"~n', [Id, Id]), 2407 fail 2408 ; true 2409 ), 2410 ( option(base_uri(Base), Options), 2411 option(write_xml_base(true), Options, true) 2412 -> xml_quote_attribute(Base, BaseText, Enc), 2413 format(Out, '~N xml:base="~w"~n', [BaseText]) 2414 ; true 2415 ), 2416 ( memberchk(document_language(Lang), Options) 2417 -> format(Out, '~N xml:lang="~w"', [Lang]) 2418 ; true 2419 ), 2420 format(Out, '>~n', []). 2421rdf_save_header(Out, FileRef, OptionsOut) :- % compatibility 2422 atom(FileRef), 2423 rdf_save_header(Out, [graph(FileRef)], OptionsOut). 2424 2425xml_encoding(Enc, Encoding) :- 2426 ( xml_encoding_name(Enc, Encoding) 2427 -> true 2428 ; throw(error(domain_error(rdf_encoding, Enc), _)) 2429 ). 2430 2431xml_encoding_name(ascii, 'US-ASCII'). 2432xml_encoding_name(iso_latin_1, 'ISO-8859-1'). 2433xml_encoding_name(utf8, 'UTF-8').
2440nsmap([], []). 2441nsmap([Id|T0], [Id=URI|T]) :- 2442 ns(Id, URI), 2443 nsmap(T0, T).
2449xml_escape_parameter_entity(In, Out) :- 2450 sub_atom(In, _, _, _, '%'), 2451 !, 2452 atom_codes(In, Codes), 2453 phrase(escape_parent(Codes), OutCodes), 2454 atom_codes(Out, OutCodes). 2455xml_escape_parameter_entity(In, In). 2456 2457escape_parent([]) --> []. 2458escape_parent([H|T]) --> 2459 ( { H == 37 } 2460 -> "%" 2461 ; [H] 2462 ), 2463 escape_parent(T).
2470header_namespaces(Options, List) :- 2471 memberchk(namespaces(NSL0), Options), 2472 !, 2473 sort([rdf,rdfs|NSL0], List). 2474header_namespaces(Options, List) :- 2475 graph(Options, DB), 2476 used_namespace_entities(List, DB).
call(Filter, Where, Prefix, URI)
The Where argument gives the location of the prefix ans is
one of subject, predicate, object or type. The
Prefix argument is the potentionally new prefix and URI is
the full URI that is being processed.
call(Goal,S,P,O,Graph)
2514:- thread_local 2515 graph_prefix/3. 2516:- meta_predicate 2517 rdf_graph_prefixes(, , ). 2518 2519rdf_graph_prefixes(Graph, List) :- 2520 rdf_graph_prefixes(Graph, List, []). 2521 2522rdf_graph_prefixes(Graph, List, M:QOptions) :- 2523 is_list(QOptions), 2524 !, 2525 meta_options(is_meta, M:QOptions, Options), 2526 option(filter(Filter), Options, true), 2527 option(expand(Expand), Options, rdf_db), 2528 option(min_count(MinCount), Options, 1), 2529 option(get_prefix(GetPrefix), Options, iri_xml_namespace), 2530 call_cleanup(prefixes(Expand, Graph, Prefixes, Filter, MinCount, GetPrefix), 2531 retractall(graph_prefix(_,_,_))), 2532 sort(Prefixes, List). 2533rdf_graph_prefixes(Graph, List, M:Filter) :- 2534 rdf_graph_prefixes(Graph, List, M:[filter(Filter)]). 2535 2536is_meta(filter). 2537is_meta(expand). 2538is_meta(get_prefix). 2539 2540 2541prefixes(Expand, Graph, Prefixes, Filter, MinCount, GetPrefix) :- 2542 ( call(Expand, S, P, O, Graph), 2543 add_ns(subject, GetPrefix, Filter, S, MinCount, s(S)), 2544 add_ns(predicate, GetPrefix, Filter, P, MinCount, sp(S,P)), 2545 add_ns_obj(GetPrefix, Filter, O, MinCount, spo(S,P,O)), 2546 fail 2547 ; true 2548 ), 2549 findall(Prefix, graph_prefix(Prefix, MinCount, _), Prefixes). 2550 2551add_ns(Where, GetPrefix, Filter, S, MinCount, Context) :- 2552 \+ rdf_is_bnode(S), 2553 call(GetPrefix, S, Full), 2554 Full \== '', 2555 !, 2556 ( graph_prefix(Full, MinCount, _) 2557 -> true 2558 ; Filter == true 2559 -> add_ns(Full, Context) 2560 ; call(Filter, Where, Full, S) 2561 -> add_ns(Full, Context) 2562 ; true 2563 ). 2564add_ns(_, _, _, _, _, _). 2565 2566add_ns(Full, Context) :- 2567 graph_prefix(Full, _, Contexts), 2568 memberchk(Context, Contexts), 2569 !. 2570add_ns(Full, Context) :- 2571 retract(graph_prefix(Full, C0, Contexts)), 2572 !, 2573 C1 is C0+1, 2574 asserta(graph_prefix(Full, C1, [Context|Contexts])). 2575add_ns(Full, _) :- 2576 ns(_, Full), 2577 !, 2578 asserta(graph_prefix(Full, _, _)). 2579add_ns(Full, Context) :- 2580 asserta(graph_prefix(Full, 1, [Context])). 2581 2582 2583add_ns_obj(GetPrefix, Filter, O, MinCount, Context) :- 2584 atom(O), 2585 !, 2586 add_ns(object, GetPrefix, Filter, O, MinCount, Context). 2587add_ns_obj(GetPrefix, Filter, literal(type(Type, _)), MinCount, _) :- 2588 atom(Type), 2589 !, 2590 add_ns(type, GetPrefix, Filter, Type, MinCount, t(Type)). 2591add_ns_obj(_, _, _, _, _).
2601used_namespace_entities(List, Graph) :- 2602 decl_used_predicate_ns(Graph), 2603 used_namespaces(List, Graph). 2604 2605used_namespaces(List, DB) :- 2606 rdf_graph_prefixes(DB, FullList), 2607 ns_abbreviations(FullList, List0), 2608 sort([rdf|List0], List). 2609 2610ns_abbreviations([], []). 2611ns_abbreviations([H0|T0], [H|T]) :- 2612 ns(H, H0), 2613 !, 2614 ns_abbreviations(T0, T). 2615ns_abbreviations([_|T0], T) :- 2616 ns_abbreviations(T0, T). 2617 2618 2619/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2620For every URL used as a predicate we *MUST* define a namespace as we 2621cannot use names holding /, :, etc. as XML identifiers. 2622- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 2623 2624:- thread_local 2625 predicate_ns/2. 2626 2627decl_used_predicate_ns(DB) :- 2628 retractall(predicate_ns(_,_)), 2629 ( rdf_current_predicate(P, DB), 2630 decl_predicate_ns(P), 2631 fail 2632 ; true 2633 ). 2634 2635decl_predicate_ns(Pred) :- 2636 predicate_ns(Pred, _), 2637 !. 2638decl_predicate_ns(Pred) :- 2639 rdf_global_id(NS:Local, Pred), 2640 xml_name(Local), 2641 !, 2642 assert(predicate_ns(Pred, NS)). 2643decl_predicate_ns(Pred) :- 2644 atom_codes(Pred, Codes), 2645 append(NSCodes, LocalCodes, Codes), 2646 xml_codes(LocalCodes), 2647 !, 2648 ( NSCodes \== [] 2649 -> atom_codes(NS, NSCodes), 2650 ( ns(Id, NS) 2651 -> assert(predicate_ns(Pred, Id)) 2652 ; between(1, infinite, N), 2653 atom_concat(ns, N, Id), 2654 \+ ns(Id, _) 2655 -> rdf_register_ns(Id, NS), 2656 print_message(informational, 2657 rdf(using_namespace(Id, NS))) 2658 ), 2659 assert(predicate_ns(Pred, Id)) 2660 ; assert(predicate_ns(Pred, -)) % no namespace used 2661 ). 2662 2663xml_codes([]). 2664xml_codes([H|T]) :- 2665 xml_code(H), 2666 xml_codes(T). 2667 2668xml_code(X) :- 2669 code_type(X, csym), 2670 !. 2671xml_code(0'-). % Match 0'-
2680rdf_save_footer(Out) :-
2681 retractall(named_anon(_, _)),
2682 retractall(inlined(_)),
2683 format(Out, '</rdf:RDF>~n', []).anon(false)
is present in the Options list.2690rdf_save_non_anon_subject(_Out, Subject, Options) :- 2691 rdf_is_bnode(Subject), 2692 ( memberchk(anon(false), Options) 2693 ; graph(Options, DB), 2694 rdf_db(_, _, Subject, DB) 2695 ), 2696 !. 2697rdf_save_non_anon_subject(Out, Subject, Options) :- 2698 rdf_save_subject(Out, Subject, Options), 2699 flag(rdf_db_saved_subjects, X, X+1).
2714rdf_save_subject(Out, Subject, Options) :- 2715 is_list(Options), 2716 !, 2717 option(base_uri(BaseURI), Options, '-'), 2718 ( rdf_save_subject(Out, Subject, BaseURI, 0, Options) 2719 -> format(Out, '~n', []) 2720 ; throw(error(rdf_save_failed(Subject), 'Internal error')) 2721 ). 2722rdf_save_subject(Out, Subject, DB) :- 2723 ( var(DB) 2724 -> rdf_save_subject(Out, Subject, []) 2725 ; rdf_save_subject(Out, Subject, [graph(DB)]) 2726 ).
2736rdf_save_subject(_, Subject, _, _, _) :- 2737 inlined(Subject), 2738 !. 2739rdf_save_subject(Out, Subject, BaseURI, Indent, Options) :- 2740 do_save_subject(Out, Subject, BaseURI, Indent, Options). 2741 2742do_save_subject(Out, Subject, BaseURI, Indent, Options) :- 2743 graph(Options, DB), 2744 findall(Pred=Object, rdf_db(Subject, Pred, Object, DB), Atts0), 2745 sort(Atts0, Atts), % remove duplicates 2746 length(Atts, L), 2747 ( length(Atts0, L0), 2748 Del is L0-L, 2749 Del > 0 2750 -> print_message(informational, 2751 rdf(save_removed_duplicates(Del, Subject))) 2752 ; true 2753 ), 2754 rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options), 2755 flag(rdf_db_saved_triples, X, X+L). 2756 2757rdf_db(Subject, Pred, Object, DB) :- 2758 var(DB), 2759 !, 2760 rdf(Subject, Pred, Object). 2761rdf_db(Subject, Pred, Object, DB) :- 2762 rdf(Subject, Pred, Object, DB:_).
2769rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options) :- 2770 rdf_equal(rdf:type, RdfType), 2771 select(RdfType=Type, Atts, Atts1), 2772 \+ rdf_is_bnode(Type), 2773 rdf_id(Type, BaseURI, TypeId), 2774 xml_is_name(TypeId), 2775 !, 2776 format(Out, '~*|<', [Indent]), 2777 rdf_write_id(Out, TypeId), 2778 save_about(Out, BaseURI, Subject, Options), 2779 save_attributes(Atts1, BaseURI, Out, TypeId, Indent, Options). 2780rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options) :- 2781 format(Out, '~*|<rdf:Description', [Indent]), 2782 save_about(Out, BaseURI, Subject, Options), 2783 save_attributes(Atts, BaseURI, Out, rdf:'Description', Indent, Options). 2784 2785xml_is_name(_NS:Atom) :- 2786 !, 2787 xml_name(Atom). 2788xml_is_name(Atom) :- 2789 xml_name(Atom).
2796save_about(Out, _BaseURI, Subject, _Options) :- 2797 rdf_is_bnode(Subject), 2798 !, 2799 ( named_anon(Subject, NodeID) 2800 -> format(Out, ' rdf:nodeID="~w"', [NodeID]) 2801 ; true 2802 ). 2803save_about(Out, BaseURI, Subject, Options) :- 2804 option(encoding(Encoding), Options, utf8), 2805 rdf_value(Subject, BaseURI, QSubject, Encoding), 2806 format(Out, ' rdf:about="~w"', [QSubject]).
2814save_attributes(Atts, BaseURI, Out, Element, Indent, Options) :-
2815 split_attributes(Atts, InTag, InBody, Options),
2816 SubIndent is Indent + 2,
2817 save_attributes2(InTag, BaseURI, tag, Out, SubIndent, Options),
2818 ( InBody == []
2819 -> format(Out, '/>~n', [])
2820 ; format(Out, '>~n', []),
2821 save_attributes2(InBody, BaseURI, body, Out, SubIndent, Options),
2822 format(Out, '~N~*|</', [Indent]),
2823 rdf_write_id(Out, Element),
2824 format(Out, '>~n', [])
2825 ).2833split_attributes(Atts, [], Atts, Options) :- 2834 option(xml_attributes(false), Options), 2835 !. 2836split_attributes(Atts, HeadAttr, BodyAttr, _) :- 2837 duplicate_attributes(Atts, Dupls, Singles), 2838 simple_literal_attributes(Singles, HeadAttr, Rest), 2839 append(Dupls, Rest, BodyAttr).
2846duplicate_attributes([], [], []). 2847duplicate_attributes([H|T], Dupls, Singles) :- 2848 H = (Name=_), 2849 named_attributes(Name, T, D, R), 2850 D \== [], 2851 append([H|D], Dupls2, Dupls), 2852 !, 2853 duplicate_attributes(R, Dupls2, Singles). 2854duplicate_attributes([H|T], Dupls2, [H|Singles]) :- 2855 duplicate_attributes(T, Dupls2, Singles). 2856 2857named_attributes(_, [], [], []) :- !. 2858named_attributes(Name, [H|T], D, R) :- 2859 ( H = (Name=_) 2860 -> D = [H|DT], 2861 named_attributes(Name, T, DT, R) 2862 ; R = [H|RT], 2863 named_attributes(Name, T, D, RT) 2864 ).
2871simple_literal_attributes([], [], []). 2872simple_literal_attributes([H|TA], [H|TI], B) :- 2873 in_tag_attribute(H), 2874 !, 2875 simple_literal_attributes(TA, TI, B). 2876simple_literal_attributes([H|TA], I, [H|TB]) :- 2877 simple_literal_attributes(TA, I, TB). 2878 2879in_tag_attribute(_=literal(Text)) :- 2880 atom(Text), % may not have lang qualifier 2881 atom_length(Text, Len), 2882 Len < 60.
2888save_attributes2([], _, _, _, _, _). 2889save_attributes2([H|T], BaseURI, Where, Out, Indent, Options) :- 2890 save_attribute(Where, H, BaseURI, Out, Indent, Options), 2891 save_attributes2(T, BaseURI, Where, Out, Indent, Options). 2892 2893save_attribute(tag, Name=literal(Value), BaseURI, Out, Indent, Options) :- 2894 AttIndent is Indent + 2, 2895 rdf_id(Name, BaseURI, NameText), 2896 option(encoding(Encoding), Options, utf8), 2897 xml_quote_attribute(Value, QVal, Encoding), 2898 format(Out, '~N~*|', [AttIndent]), 2899 rdf_write_id(Out, NameText), 2900 format(Out, '="~w"', [QVal]). 2901save_attribute(body, Name=literal(Literal0), BaseURI, Out, Indent, Options) :- 2902 !, 2903 rdf_id(Name, BaseURI, NameText), 2904 ( memberchk(convert_typed_literal(Converter), Options), 2905 call(Converter, Type, Content, Literal0) 2906 -> Literal = type(Type, Content) 2907 ; Literal = Literal0 2908 ), 2909 save_body_literal(Literal, NameText, BaseURI, Out, Indent, Options). 2910save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2911 rdf_is_bnode(Value), 2912 !, 2913 rdf_id(Name, BaseURI, NameText), 2914 format(Out, '~N~*|<', [Indent]), 2915 rdf_write_id(Out, NameText), 2916 ( named_anon(Value, NodeID) 2917 -> format(Out, ' rdf:nodeID="~w"/>', [NodeID]) 2918 ; ( rdf(S1, Name, Value), 2919 rdf(S2, P2, Value), 2920 (S1 \== S2 ; Name \== P2) 2921 -> predicate_property(named_anon(_,_), number_of_clauses(N)), 2922 atom_concat('bn', N, NodeID), 2923 assertz(named_anon(Value, NodeID)) 2924 ; true 2925 ), 2926 SubIndent is Indent + 2, 2927 ( rdf_collection(Value) 2928 -> save_about(Out, BaseURI, Value, Options), 2929 format(Out, ' rdf:parseType="Collection">~n', []), 2930 rdf_save_list(Out, Value, BaseURI, SubIndent, Options) 2931 ; format(Out, '>~n', []), 2932 rdf_save_subject(Out, Value, BaseURI, SubIndent, Options) 2933 ), 2934 format(Out, '~N~*|</', [Indent]), 2935 rdf_write_id(Out, NameText), 2936 format(Out, '>~n', []) 2937 ). 2938save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2939 option(inline(true), Options), 2940 has_attributes(Value, Options), 2941 \+ inlined(Value), 2942 !, 2943 assertz(inlined(Value)), 2944 rdf_id(Name, BaseURI, NameText), 2945 format(Out, '~N~*|<', [Indent]), 2946 rdf_write_id(Out, NameText), 2947 SubIndent is Indent + 2, 2948 ( rdf_collection(Value) 2949 -> save_about(Out, BaseURI, Value, Options), 2950 format(Out, ' rdf:parseType="Collection">~n', []), 2951 rdf_save_list(Out, Value, BaseURI, SubIndent, Options) 2952 ; format(Out, '>~n', []), 2953 do_save_subject(Out, Value, BaseURI, SubIndent, Options) 2954 ), 2955 format(Out, '~N~*|</', [Indent]), 2956 rdf_write_id(Out, NameText), 2957 format(Out, '>~n', []). 2958save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2959 option(encoding(Encoding), Options, utf8), 2960 rdf_value(Value, BaseURI, QVal, Encoding), 2961 rdf_id(Name, BaseURI, NameText), 2962 format(Out, '~N~*|<', [Indent]), 2963 rdf_write_id(Out, NameText), 2964 format(Out, ' rdf:resource="~w"/>', [QVal]). 2965 2966has_attributes(URI, Options) :- 2967 graph(Options, DB), 2968 rdf_db(URI, _, _, DB), 2969 !.
2974save_body_literal(lang(Lang, Value), 2975 NameText, BaseURI, Out, Indent, Options) :- 2976 !, 2977 format(Out, '~N~*|<', [Indent]), 2978 rdf_write_id(Out, NameText), 2979 ( memberchk(document_language(Lang), Options) 2980 -> write(Out, '>') 2981 ; rdf_id(Lang, BaseURI, LangText), 2982 format(Out, ' xml:lang="~w">', [LangText]) 2983 ), 2984 save_attribute_value(Value, Out, Options), 2985 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 2986save_body_literal(type(Type, DOM), 2987 NameText, _BaseURI, Out, Indent, Options) :- 2988 rdf_equal(Type, rdf:'XMLLiteral'), 2989 !, 2990 ( atom(DOM) 2991 -> format(Out, '~N~*|<', [Indent]), 2992 rdf_write_id(Out, NameText), 2993 format(Out, ' rdf:parseType="Literal">~w</', [DOM]), 2994 rdf_write_id(Out, NameText), write(Out, '>') 2995 ; save_xml_literal(DOM, NameText, Out, Indent, Options) 2996 ). 2997save_body_literal(type(Type, Value), 2998 NameText, BaseURI, Out, Indent, Options) :- 2999 !, 3000 format(Out, '~N~*|<', [Indent]), 3001 rdf_write_id(Out, NameText), 3002 option(encoding(Encoding), Options, utf8), 3003 rdf_value(Type, BaseURI, QVal, Encoding), 3004 format(Out, ' rdf:datatype="~w">', [QVal]), 3005 save_attribute_value(Value, Out, Options), 3006 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 3007save_body_literal(Literal, 3008 NameText, _, Out, Indent, Options) :- 3009 atomic(Literal), 3010 !, 3011 format(Out, '~N~*|<', [Indent]), 3012 rdf_write_id(Out, NameText), 3013 write(Out, '>'), 3014 save_attribute_value(Literal, Out, Options), 3015 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 3016save_body_literal(DOM, 3017 NameText, BaseURI, Out, Indent, Options) :- 3018 rdf_equal(Type, rdf:'XMLLiteral'), 3019 save_body_literal(type(Type, DOM), 3020 NameText, BaseURI, Out, Indent, Options). 3021 3022save_attribute_value(Value, Out, Options) :- % strings 3023 ( atom(Value) 3024 ; string(Value) 3025 ), 3026 !, 3027 option(encoding(Encoding), Options, utf8), 3028 xml_quote_cdata(Value, QVal, Encoding), 3029 write(Out, QVal). 3030save_attribute_value(Value, Out, _Options) :- % numbers 3031 number(Value), 3032 !, 3033 writeq(Out, Value). % quoted: preserve floats 3034save_attribute_value(Value, _Out, _Options) :- 3035 throw(error(save_attribute_value(Value), _)).
<prop parseType="literal"
but not the terminating >. We need to establish the
namespaces used in the DOM. The namespaces in the rdf document
are in the nsmap-option of Options.
3049save_xml_literal(DOM, Attr, Out, Indent, Options) :- 3050 xml_is_dom(DOM), 3051 !, 3052 memberchk(nsmap(NsMap), Options), 3053 id_to_atom(Attr, Atom), 3054 xml_write(Out, 3055 element(Atom, ['rdf:parseType'='Literal'], DOM), 3056 [ header(false), 3057 indent(Indent), 3058 nsmap(NsMap) 3059 ]). 3060save_xml_literal(NoDOM, _, _, _, _) :- 3061 must_be(xml_dom, NoDOM). 3062 3063id_to_atom(NS:Local, Atom) :- 3064 !, 3065 atomic_list_concat([NS,Local], :, Atom). 3066id_to_atom(ID, ID).
3076:- rdf_meta 3077 rdf_collection(r), 3078 collection_p(r,r). 3079 3080rdf_collection(rdf:nil) :- !. 3081rdf_collection(Cell) :- 3082 rdf_is_bnode(Cell), 3083 findall(F, rdf(Cell, rdf:first, F), [_]), 3084 findall(F, rdf(Cell, rdf:rest, F), [Rest]), 3085 forall(rdf(Cell, P, V), 3086 collection_p(P, V)), 3087 rdf_collection(Rest). 3088 3089collection_p(rdf:first, V) :- atom(V). 3090collection_p(rdf:rest, _). 3091collection_p(rdf:type, rdf:'List').
3096rdf_save_list(_, List, _, _, _) :- 3097 rdf_equal(List, rdf:nil), 3098 !. 3099rdf_save_list(Out, List, BaseURI, Indent, Options) :- 3100 rdf_has(List, rdf:first, First), 3101 ( rdf_is_bnode(First) 3102 -> nl(Out), 3103 rdf_save_subject(Out, First, BaseURI, Indent, Options) 3104 ; option(encoding(Encoding), Options, utf8), 3105 rdf_value(First, BaseURI, QVal, Encoding), 3106 format(Out, '~N~*|<rdf:Description rdf:about="~w"/>', 3107 [Indent, QVal]) 3108 ), 3109 flag(rdf_db_saved_triples, X, X+3), 3110 ( rdf_has(List, rdf:rest, List2), 3111 \+ rdf_equal(List2, rdf:nil) 3112 -> rdf_save_list(Out, List2, BaseURI, Indent, Options) 3113 ; true 3114 ).
3122rdf_id(Id, BaseURI, Local) :- 3123 assertion(atom(BaseURI)), 3124 atom_concat(BaseURI, Local, Id), 3125 sub_atom(Local, 0, 1, _, #), 3126 !. 3127rdf_id(Id, _, NS:Local) :- 3128 iri_xml_namespace(Id, Full, Local), 3129 ns(NS, Full), 3130 !. 3131rdf_id(Id, _, NS:Local) :- 3132 ns(NS, Full), 3133 Full \== '', 3134 atom_concat(Full, Local, Id), 3135 !. 3136rdf_id(Id, _, Id).
3144rdf_write_id(Out, NS:Local) :- 3145 !, 3146 format(Out, '~w:~w', [NS, Local]). 3147rdf_write_id(Out, Atom) :- 3148 write(Out, Atom).
3157rdf_value(Base, Base, '', _) :- !. 3158rdf_value(V, Base, Text, Encoding) :- 3159 atom_concat(Base, Local, V), 3160 sub_atom(Local, 0, _, _, #), 3161 !, 3162 xml_quote_attribute(Local, Text, Encoding). 3163rdf_value(V, _, Text, Encoding) :- 3164 ns(NS, Full), 3165 atom_concat(Full, Local, V), 3166 xml_is_name(Local), 3167 !, 3168 xml_quote_attribute(Local, QLocal, Encoding), 3169 atomic_list_concat(['&', NS, (';'), QLocal], Text). 3170rdf_value(V, _, Q, Encoding) :- 3171 xml_quote_attribute(V, Q, Encoding). 3172 3173 3174 /******************************* 3175 * MATCH AND COMPARE * 3176 *******************************/
icase, substring, word, prefix or like. For backward
compatibility, exact is a synonym for icase.3199 /******************************* 3200 * DEPRECATED MATERIAL * 3201 *******************************/
3211rdf_split_url(Prefix, Local, URL) :- 3212 atomic(URL), 3213 !, 3214 iri_xml_namespace(URL, Prefix, Local). 3215rdf_split_url(Prefix, Local, URL) :- 3216 atom_concat(Prefix, Local, URL).
3224rdf_url_namespace(URL, Prefix) :- 3225 iri_xml_namespace(URL, Prefix). 3226 3227 3228 /******************************* 3229 * LITERALS * 3230 *******************************/
rdf_litindex.pl.not(Key). If not-terms are provided, there
must be at least one positive keywords. The negations are tested
after establishing the positive matches.key(+Key)
Succeeds if Key is a key in the map and unify Answer with the
number of values associated with the key. This provides a fast
test of existence without fetching the possibly large
associated value set as with rdf_find_literal_map/3.prefix(+Prefix)
Unify Answer with an ordered set of all keys that have the
given prefix. See section 3.1 for details on prefix matching.
Prefix must be an atom. This call is intended for
auto-completion in user interfaces.ge(+Min)
Unify Answer with all keys that are larger or equal to the
integer Min.le(+Max)
Unify Answer with all keys that are smaller or equal to the integer
Max.between(+Min, +Max) Unify
Answer with all keys between Min and Max (including).3318 /******************************* 3319 * MISC * 3320 *******************************/
Major*10000 + Minor*100 + Patch.
s,
p, sp, o, po, spo, g, sg or pg. Parameter
is one of:
permission_error exception.When inside a transaction, Generation is unified to a term TransactionStartGen + InsideTransactionGen. E.g., 4+3 means that the transaction was started at generation 4 of the global database and we have created 3 new generations inside the transaction. Note that this choice of representation allows for comparing generations using Prolog arithmetic. Comparing a generation in one transaction with a generation in another transaction is meaningless.
3417 /******************************* 3418 * MESSAGES * 3419 *******************************/ 3420 3421:- multifile 3422 prolog:message//1. 3423 3424prologmessage(rdf(Term)) --> 3425 message(Term). 3426 3427message(loaded(How, What, BaseURI, Triples, Time)) --> 3428 how(How), 3429 source(What), 3430 into(What, BaseURI), 3431 in_time(Triples, Time). 3432message(save_removed_duplicates(N, Subject)) --> 3433 [ 'Removed ~d duplicate triples about "~p"'-[N,Subject] ]. 3434message(saved(File, SavedSubjects, SavedTriples)) --> 3435 [ 'Saved ~D triples about ~D subjects into ~p'- 3436 [SavedTriples, SavedSubjects, File] 3437 ]. 3438message(using_namespace(Id, NS)) --> 3439 [ 'Using namespace id ~w for ~w'-[Id, NS] ]. 3440message(inconsistent_cache(DB, Graphs)) --> 3441 [ 'RDF cache file for ~w contains the following graphs'-[DB], nl, 3442 '~t~8|~p'-[Graphs] 3443 ]. 3444message(guess_format(Ext)) --> 3445 [ 'Unknown file-extension: ~w. Assuming RDF/XML'-[Ext] ]. 3446message(meta(not_expanded(G))) --> 3447 [ 'rdf_meta/1: ~p is not expanded'-[G] ]. 3448message(deprecated(rdf_unload(Graph))) --> 3449 [ 'rdf_unload/1: Use ~q'-[rdf_unload_graph(Graph)] ]. 3450 3451 3452how(load) --> [ 'Loaded' ]. 3453how(parsed) --> [ 'Parsed' ]. 3454 3455source(SourceURL) --> 3456 { uri_file_name(SourceURL, File), 3457 !, 3458 file_base_name(File, Base) % TBD: relative file? 3459 }, 3460 [ ' "~w"'-[Base] ]. 3461source(SourceURL) --> 3462 [ ' "~w"'-[SourceURL] ]. 3463 3464into(_, _) --> []. % TBD 3465 3466in_time(Triples, ParseTime) --> 3467 [ ' in ~2f sec; ~D triples'-[ParseTime, Triples] 3468 ]
Core RDF database
The file library(semweb/rdf_db) provides the core of the SWI-Prolog RDF store.