fix: unaccent in trigram title search and index

apps/server/src/core/search/search.service.ts

@@ -48,7 +48,7 @@ export class SearchService {
     const rankColumn = browseByFilters
       ? sql<number>`0`.as('rank')
       : titleOnly
-        ? sql<number>`word_similarity(lower(${titleQuery}), lower(pages.title))`.as(
+        ? sql<number>`word_similarity(lower(f_unaccent(${titleQuery})), lower(f_unaccent(pages.title)))`.as(
             'rank',
           )
         : sql<number>`ts_rank(tsv, to_tsquery('english', f_unaccent(${searchQuery})))`.as(
@@ -84,9 +84,9 @@ export class SearchService {
       .$if(!browseByFilters && titleOnly, (qb) =>
         qb.where((eb) =>
           eb(
-            sql`lower(pages.title)`,
+            sql`lower(f_unaccent(pages.title))`,
             'like',
-            sql`lower(${`%${titleLikeQuery}%`})`,
+            sql`lower(f_unaccent(${`%${titleLikeQuery}%`}))`,
           ),
         ),
       )

apps/server/src/database/migrations/20260824T211732-page-title-trgm-index.ts

@@ -1,12 +1,34 @@
 import { type Kysely, sql } from 'kysely';
 
 export async function up(db: Kysely<any>): Promise<void> {
-  await sql`CREATE INDEX IF NOT EXISTS pages_title_trgm_idx ON pages USING gin (lower(title) gin_trgm_ops)`.execute(
+  // f_unaccent must be schema-qualified in its body to be usable inside an index
+  // expression: Postgres 15+ builds indexes under a secured search_path
+  // (pg_catalog, pg_temp), so an unqualified unaccent() cannot be resolved during
+  // CREATE INDEX. Redefine f_unaccent in place (in whatever schema it already
+  // lives) with the unaccent function and dictionary both qualified.
+  await sql`
+    DO $migration$
+    DECLARE ext_schema text;
+    BEGIN
+    SELECT n.nspname INTO ext_schema
+    FROM pg_extension e JOIN pg_namespace n ON n.oid = e.extnamespace
+    WHERE e.extname = 'unaccent';
+
+    EXECUTE format(
+      'CREATE OR REPLACE FUNCTION f_unaccent(text) RETURNS text '
+        || 'LANGUAGE sql IMMUTABLE PARALLEL SAFE STRICT '
+        || 'AS $f$ SELECT %I.unaccent(%L::regdictionary, $1) $f$',
+      ext_schema, ext_schema || '.unaccent');
+    END
+    $migration$;
+  `.execute(db);
+
+  await sql`CREATE INDEX IF NOT EXISTS pages_title_trgm_idx ON pages USING gin (lower(f_unaccent(title)) gin_trgm_ops)`.execute(
     db,
   );
 
   // separators normalized to spaces so space-typed queries match How_to_export.pdf
-  await sql`CREATE INDEX IF NOT EXISTS attachments_file_name_trgm_idx ON attachments USING gin (lower(translate(file_name, '_.-', '   ')) gin_trgm_ops)`.execute(
+  await sql`CREATE INDEX IF NOT EXISTS attachments_file_name_trgm_idx ON attachments USING gin (lower(f_unaccent(translate(file_name, '_.-', '   '))) gin_trgm_ops)`.execute(
     db,
   );
 }