This HTML5 document contains 31 embedded RDF statements represented using HTML+Microdata notation.

The embedded RDF content will be recognized by any processor of HTML5 Microdata.

Subject Item

n9:this

foaf:made

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

Subject Item

n13:this

sioc:creator_of

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

Subject Item

n5:item

n6:services_of

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

Subject Item

n7:this

sioc:creator_of

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

Subject Item

n2:VOS

sioc:container_of

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

atom:entry

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

atom:contains

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

Subject Item

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

rdf:type

sioct:Comment atom:Entry

dcterms:created

2017-06-13T05:46:13.803095

dcterms:modified

2017-06-29T07:41:35.193181

rdfs:label

VirtTipsAndTricksGuideDumpAndReloadGraphs

foaf:maker

n9:this n16:this

dc:title

VirtTipsAndTricksGuideDumpAndReloadGraphs

opl:isDescribedUsing

n15:rdf

sioc:has_creator

n13:this n7:this

sioc:content

%META:TOPICPARENT{name="VirtTipsAndTricksGuide"}% ---+ RDF dumps from Virtuoso Quad store hosted data Every DBMS needs to offer a mechanism for bulk export and import of data. Virtuoso supports dumping and reloading graph model data (e.g., RDF), as well as relational data (e.g., SQL) (discussed elsewhere). %TOC% ---++ How is it done? We have created stored procedures for the task. The dump procedures leverage SPARQL to facilitate selective data dump(s) from one or more Named Graphs, each denoted by an IRI. ---+++ Dump One Graph <verbatim> CREATE PROCEDURE dump_one_graph ( IN srcgraph VARCHAR , IN out_file VARCHAR , IN file_length_limit INTEGER := 1000000000 ) { DECLARE file_name VARCHAR; DECLARE env, ses ANY; DECLARE ses_len, max_ses_len, file_len, file_idx INTEGER; SET ISOLATION = 'uncommitted'; max_ses_len := 10000000; file_len := 0; file_idx := 1; file_name := sprintf ('%s%06d.ttl', out_file, file_idx); string_to_file ( file_name || '.graph', srcgraph, -2 ); string_to_file ( file_name, sprintf ( '# Dump of graph <%s>, as of %s\n', srcgraph, CAST (NOW() AS VARCHAR) ), -2 ); env := vector (dict_new (16000), 0, '', '', '', 0, 0, 0, 0); ses := string_output (); FOR (SELECT * FROM ( SPARQL DEFINE input:storage "" SELECT ?s ?p ?o { GRAPH `iri(?:srcgraph)` { ?s ?p ?o } } ) AS sub OPTION (LOOP)) DO { http_ttl_triple (env, "s", "p", "o", ses); ses_len := length (ses); IF (ses_len > max_ses_len) { file_len := file_len + ses_len; IF (file_len > file_length_limit) { http (' .\n', ses); string_to_file (file_name, ses, -1); file_len := 0; file_idx := file_idx + 1; file_name := sprintf ('%s%06d.ttl', out_file, file_idx); string_to_file ( file_name, sprintf ( '# Dump of graph <%s>, as of %s (part %d)\n', srcgraph, CAST (NOW() AS VARCHAR), file_idx), -2 ); env := VECTOR (dict_new (16000), 0, '', '', '', 0, 0, 0, 0); } ELSE string_to_file (file_name, ses, -1); ses := string_output (); } } IF (LENGTH (ses)) { http (' .\n', ses); string_to_file (file_name, ses, -1); } } ; </verbatim> ---+++ Dump Multiple Graphs <verbatim> CREATE PROCEDURE dump_graphs ( IN dir VARCHAR := 'dumps' , IN file_length_limit INTEGER := 1000000000 ) { DECLARE inx INT; inx := 1; SET ISOLATION = 'uncommitted'; FOR ( SELECT * FROM ( SPARQL DEFINE input:storage "" SELECT DISTINCT ?g { GRAPH ?g { ?s ?p ?o } . FILTER ( ?g != virtrdf: ) } ) AS sub OPTION ( LOOP )) DO { dump_one_graph ( "g", sprintf ('%s/graph%06d_', dir, inx), file_length_limit ); inx := inx + 1; } } ; </verbatim> ---+++ Load Graphs This stored procedure performs a bulk load from a file. <verbatim> CREATE PROCEDURE load_graphs ( IN dir VARCHAR := 'dumps/' ) { DECLARE arr ANY; DECLARE g VARCHAR; arr := sys_dirlist (dir, 1); log_enable (2, 1); FOREACH (VARCHAR f IN arr) DO { IF (f LIKE '*.ttl') { DECLARE CONTINUE HANDLER FOR SQLSTATE '*' { log_message (sprintf ('Error in %s', f)); }; g := file_to_string (dir || '/' || f || '.graph'); DB.DBA.TTLP_MT (file_open (dir || '/' || f), g, g, 255); } } EXEC ('checkpoint'); }; </verbatim> ---++ Example 1. Call the <code><nowiki>dump_one_graph</nowiki></code> procedure, for ex. with the following values: <verbatim> SQL> dump_one_graph ('http://daas.openlinksw.com/data#', './data_', 1000000000); Done. -- 1438 msec. </verbatim> 1. As a result, a dump of the graph <http://daas.openlinksw.com/data#> will be found in the files <code>data_XX</code> (located in your Virtuoso db folder): <verbatim> data_000001.ttl data_000002.ttl .... data_000001.ttl.graph </verbatim> ---++ Related * [[VirtTipsAndTricksGuide][Virtuoso Tips and Tricks Collection]] * [[VirtDumpLoadRdfGraphs][Virtuoso Scripts to Dump and Reload RDF Graphs - more examples]] * [[http://docs.openlinksw.com/virtuoso/rdfperformancetuning.html#rdfperfdumpandreloadgraphs][Virtuoso Documentation]]

sioc:id

2b4149c655e45f334ac6eb30a24fcab1

sioc:link

n4:VirtTipsAndTricksGuideDumpAndReloadGraphs

sioc:has_container

n2:VOS

n6:has_services

n5:item

atom:title

VirtTipsAndTricksGuideDumpAndReloadGraphs

sioc:links_to

n4:VirtDumpLoadRdfGraphs n12:rdfperfdumpandreloadgraphs

atom:source

n2:VOS

atom:author

n9:this

atom:published

2017-06-13T05:46:13Z

atom:updated

2017-06-29T07:41:35Z

sioc:topic

n2:VOS