Fix IRI generation by sanitizing column names with spaces.

Regenerate graph-01.ttl and graph-02.ttl with the corrected output.

src/map/step_01.rs

@@ -79,10 +79,19 @@ fn class_iri(table: &str) -> SimpleTerm<'static> {
     )
 }
 
+fn sanitize_name(name: &str) -> String {
+    let s: String = name
+        .chars()
+        .map(|c| if c.is_ascii_alphanumeric() || c == '-' { c } else { '_' })
+        .collect();
+    let s = s.replace("__", "_");
+    s.trim_matches('_').to_string()
+}
+
 fn column_iri(table: &str, column: &str) -> SimpleTerm<'static> {
     SimpleTerm::Iri(
         sophia::api::term::IriRef::new_unchecked(
-            format!("{}{}#{}", BASE_IRI, table, column).into(),
+            format!("{}{}#{}", BASE_IRI, table, sanitize_name(column)).into(),
         ),
     )
 }
@@ -90,7 +99,7 @@ fn column_iri(table: &str, column: &str) -> SimpleTerm<'static> {
 fn ref_iri(table: &str, fk_col: &str) -> SimpleTerm<'static> {
     SimpleTerm::Iri(
         sophia::api::term::IriRef::new_unchecked(
-            format!("{}{}#ref-{}", BASE_IRI, table, fk_col).into(),
+            format!("{}{}#ref-{}", BASE_IRI, table, sanitize_name(fk_col)).into(),
         ),
     )
 }