Upgrade to FTS4 with unicode61

android/database/src/main/assets/MagicHomeInventory.schema.sql

@@ -673,8 +673,11 @@ CREATE VIEW Item_Path AS
 	join Category       c   ON i.category = c._id
 ;
 
-
-CREATE VIRTUAL TABLE Search USING FTS3 (
+-- FTS4 available since Android 3.0 (API 11) SQLite 3.7.4: https://www.sqlite.org/releaselog/3_7_4.html
+-- Current minimum is Android 5.0 (API 21) SQLite 3.8.6: https://www.sqlite.org/releaselog/3_8_6.html,
+-- which means "The unicode61 tokenizer is now included in FTS4 by default."
+CREATE VIRTUAL TABLE Search USING FTS4 (
+	tokenize=unicode61 'remove_diacritics=2',
 	name,
 	location
 );

android/database/src/main/assets/MagicHomeInventory.upgrade.6.sql

@@ -0,0 +1,15 @@
+-- Context: https://github.com/TWiStErRob/net.twisterrob.inventory/issues/170
+-- FTS3 supported only ASCII characters, FTS4 supports unicode when used with unicode61 tokenizer.
+
+-- Recreate the Search table with new FTS4 format.
+DROP TABLE IF EXISTS Search;
+CREATE VIRTUAL TABLE Search USING FTS4 (
+	tokenize=unicode61 'remove_diacritics=2',
+	name,
+	location
+);
+
+-- Re-insert all data into the new table.
+INSERT INTO Search_Refresher (_id) SELECT _id FROM Item;
+-- Compact database indexes for faster search experience.
+INSERT INTO Search(Search) VALUES('optimize');

android/database/src/main/java/net/twisterrob/inventory/android/content/Database.java

@@ -39,7 +39,7 @@ public Database(Context context) {
 	@VisibleForTesting
 	public Database(Context hostContext, Resources resources) {
 		super(resources);
-		m_helper = new DatabaseOpenHelper(hostContext, NAME, 5, BuildConfig.DEBUG) {
+		m_helper = new DatabaseOpenHelper(hostContext, NAME, 6, BuildConfig.DEBUG) {
 			@Override public void onConfigure(SQLiteDatabase db) {
 				super.onConfigure(db);
 				// CONSIDER enabling auto_vacuum=INCREMENTAL as it speeds up a large delete a lot