add text handling to loading and showing triples

pgsql/fload.sql

@@ -6,6 +6,8 @@ begin
   case tname
     when 'node' then
       return get_node(vtext);
+    when 'text' then
+      return get_text(vtext);
     when 'int' then
       return to_number(vtext, '99999999');
     else
@@ -35,6 +37,18 @@ end;
 $$ language plpgsql;
 
 
+create or replace function get_text(vtext text, out value bigint) as $$
+begin
+  select texts.id into value from texts
+    where text = vtext;
+  if not found then 
+      insert into texts (text) values (vtext)
+        returning texts.id into value;
+  end if;
+end;
+$$ language plpgsql;
+
+
 create or replace function load_triple(
     stname text, stext text, ptext text,
     otname text, otext text, event bigint) returns bigint as $$
@@ -74,13 +88,15 @@ $$ language plpgsql;
 create or replace function load_namespace(
         nsiri text, nspfx text, out nsid int) as $$
 begin
-  select ns.id into nsid from namespaces ns
-    where iri = nsiri and prefix = nspfx;
-  if not found then
+  nsid := get_nsiri(nsiri);
+  if nsid is null then
+    nsid := get_nsprefix(nspfx);
+    if nsid is null then
       insert into namespaces as ns (iri, prefix)
         values (nsiri, nspfx)
         returning ns.id into nsid;
     end if;
+  end if;
 end;
 $$ language plpgsql;
 
@@ -111,6 +127,16 @@ $$ language plpgsql;
 
 -- simple SQL functions
 
+create or replace function get_nsiri(nsiri text) returns int as $$
+  select ns.id from namespaces ns where iri = nsiri;
+$$ language sql;
+
+
+create or replace function get_nsprefix(nspfx text) returns int as $$
+  select ns.id from namespaces ns where prefix = nspfx;
+$$ language sql;
+
+
 create or replace function get_datatype(name text) returns smallint as $$
   select dt.id from datatypes dt where dtname = name;
 $$ language sql;

pgsql/fshow.sql

@@ -13,6 +13,8 @@ begin
   case tname
     when 'node' then
       return show_node(id);
+    when 'text' then
+      return show_text(id);
     else 
       return text(show_value.id);
   end case;
@@ -27,3 +29,7 @@ create or replace function show_node(nid bigint) returns text as $$
 $$ language sql;
 
 
+create or replace function show_text(tid bigint) returns text as $$
+  select text from texts
+    where texts.id = tid;
+$$ language sql;

pgsql/lbase.sql

@@ -6,6 +6,7 @@ select new_event() as event
 
 -- load data
 
+select load_namespace('http://cyberconcepts.org/cco-blank#', '_');
 select load_namespace('http://cyberconcepts.org/cco-common#', 'cco');
 select load_namespace('http://www.w3.org/1999/02/22-rdf-syntax-ns#', 'rdf');
 select load_namespace('http://www.w3.org/2000/01/rdf-schema#', 'rdfs');
@@ -26,3 +27,4 @@ select load_datatype('timestamp');
 select load_triple('node', 'rdf:type', 'rdf:type', 'node', 'rdf:Property', :event);
 select load_triple('node', 'rdf:Property', 'rdf:type', 'node', 'rdfs:Class', :event);
 select load_triple('node', 'rdfs:Class', 'rdf:type', 'node', 'rdfs:Class', :event);
+select load_triple('node', 'rdfs:label', 'rdf:type', 'node', 'rdfs:Property', :event);

pgsql/tcreate.sql

@@ -4,7 +4,7 @@
 CREATE TABLE namespaces (
     id serial NOT NULL primary key,
     iri text NOT NULL unique,
-    prefix text unique
+    prefix text NOT NULL unique
 );
 
 CREATE TABLE datatypes (
@@ -68,4 +68,4 @@ CREATE INDEX idx_po ON triples USING btree (predicate, otype, ovalue);
 CREATE INDEX idx_os ON triples USING btree (otype, ovalue, stype, svalue);
 
 CREATE INDEX fki_language ON texts USING btree (language);
-CREATE INDEX idx_texts ON texts USING btree (text);
+CREATE INDEX idx_text ON texts USING btree (text);

pgsql/vtriples.sql

@@ -6,7 +6,7 @@ select triples.id,
        stype, svalue, show_value(stype, svalue) as stext, 
        predicate, show_value(dt.id, predicate) as ptext, 
        otype, ovalue, show_value(otype, ovalue) as otext,
-       events.tstamp as ts
+       to_char(events.tstamp, 'YYYY-MM-DD HH24:MI:SS') as ts
   from triples, datatypes dt, events
   where dtname = 'node'
     and events.id = creation