do not use trigger but delete message index entries manually

src/main/java/eu/siacs/conversations/persistance/DatabaseBackend.java

@@ -35,6 +35,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArrayList;
+
 import org.json.JSONException;
 
 import eu.siacs.conversations.Config;
@@ -59,11 +60,9 @@ import rocks.xmpp.addr.Jid;
 
 public class DatabaseBackend extends SQLiteOpenHelper {
 
-	private static DatabaseBackend instance = null;
-
 	private static final String DATABASE_NAME = "history";
-	private static final int DATABASE_VERSION = 41;
+	private static final int DATABASE_VERSION = 42;
-
+	private static DatabaseBackend instance = null;
 	private static String CREATE_CONTATCS_STATEMENT = "create table "
 			+ Contact.TABLENAME + "(" + Contact.ACCOUNT + " TEXT, "
 			+ Contact.SERVERNAME + " TEXT, " + Contact.SYSTEMNAME + " TEXT,"
@@ -168,13 +167,26 @@ public class DatabaseBackend extends SQLiteOpenHelper {
 	private static String CREATE_MESSAGE_INDEX_TABLE = "CREATE VIRTUAL TABLE messages_index USING FTS4(uuid TEXT PRIMARY KEY, body TEXT)";
 	private static String CREATE_MESSAGE_INSERT_TRIGGER = "CREATE TRIGGER after_message_insert AFTER INSERT ON " + Message.TABLENAME + " BEGIN INSERT INTO messages_index (uuid,body) VALUES (new.uuid,new.body); END;";
 	private static String CREATE_MESSAGE_UPDATE_TRIGGER = "CREATE TRIGGER after_message_update UPDATE of uuid,body ON " + Message.TABLENAME + " BEGIN update messages_index set body=new.body,uuid=new.uuid WHERE uuid=old.uuid; END;";
-	private static String CREATE_MESSAGE_DELETE_TRIGGER = "CREATE TRIGGER after_message_delete AFTER DELETE ON "+Message.TABLENAME+ " BEGIN DELETE from messages_index where uuid=old.uuid; END;";
 	private static String COPY_PREEXISTING_ENTRIES = "INSERT into messages_index(uuid,body) select uuid,body FROM " + Message.TABLENAME + ";";
 
 	private DatabaseBackend(Context context) {
 		super(context, DATABASE_NAME, null, DATABASE_VERSION);
 	}
 
+	private static ContentValues createFingerprintStatusContentValues(FingerprintStatus.Trust trust, boolean active) {
+		ContentValues values = new ContentValues();
+		values.put(SQLiteAxolotlStore.TRUST, trust.toString());
+		values.put(SQLiteAxolotlStore.ACTIVE, active ? 1 : 0);
+		return values;
+	}
+
+	public static synchronized DatabaseBackend getInstance(Context context) {
+		if (instance == null) {
+			instance = new DatabaseBackend(context);
+		}
+		return instance;
+	}
+
 	@Override
 	public void onCreate(SQLiteDatabase db) {
 		db.execSQL("PRAGMA foreign_keys=ON;");
@@ -234,7 +246,6 @@ public class DatabaseBackend extends SQLiteOpenHelper {
 		db.execSQL(CREATE_MESSAGE_INDEX_TABLE);
 		db.execSQL(CREATE_MESSAGE_INSERT_TRIGGER);
 		db.execSQL(CREATE_MESSAGE_UPDATE_TRIGGER);
-		db.execSQL(CREATE_MESSAGE_DELETE_TRIGGER);
 	}
 
 	@Override
@@ -495,16 +506,12 @@ public class DatabaseBackend extends SQLiteOpenHelper {
 			db.execSQL(CREATE_MESSAGE_INDEX_TABLE);
 			db.execSQL(CREATE_MESSAGE_INSERT_TRIGGER);
 			db.execSQL(CREATE_MESSAGE_UPDATE_TRIGGER);
-			db.execSQL(CREATE_MESSAGE_DELETE_TRIGGER);
 			db.execSQL(COPY_PREEXISTING_ENTRIES);
 		}
-	}
 
-	private static ContentValues createFingerprintStatusContentValues(FingerprintStatus.Trust trust, boolean active) {
+		if (oldVersion < 42 && newVersion >= 42) {
-		ContentValues values = new ContentValues();
+			db.execSQL("DROP TRIGGER IF EXISTS after_message_delete");
-		values.put(SQLiteAxolotlStore.TRUST,trust.toString());
+		}
-		values.put(SQLiteAxolotlStore.ACTIVE,active ? 1 : 0);
-		return values;
 	}
 
 	private void canonicalizeJids(SQLiteDatabase db) {
@@ -586,13 +593,6 @@ public class DatabaseBackend extends SQLiteOpenHelper {
 		cursor.close();
 	}
 
-	public static synchronized DatabaseBackend getInstance(Context context) {
-		if (instance == null) {
-			instance = new DatabaseBackend(context);
-		}
-		return instance;
-	}
-
 	public void createConversation(Conversation conversation) {
 		SQLiteDatabase db = this.getWritableDatabase();
 		db.insert(Conversation.TABLENAME, null, conversation.getContentValues());
@@ -909,16 +909,23 @@ public class DatabaseBackend extends SQLiteOpenHelper {
 	public void deleteMessagesInConversation(Conversation conversation) {
 		long start = SystemClock.elapsedRealtime();
 		final SQLiteDatabase db = this.getWritableDatabase();
+		db.beginTransaction();
 		String[] args = {conversation.getUuid()};
+		db.delete("messages_index", "uuid in (select uuid from messages where conversationUuid=?)", args);
 		int num = db.delete(Message.TABLENAME, Message.CONVERSATION + "=?", args);
+		db.setTransactionSuccessful();
+		db.endTransaction();
 		Log.d(Config.LOGTAG, "deleted " + num + " messages for " + conversation.getJid().asBareJid() + " in " + (SystemClock.elapsedRealtime() - start) + "ms");
 	}
 
-	public boolean expireOldMessages(long timestamp) {
+	public void expireOldMessages(long timestamp) {
-		String where = Message.TIME_SENT+"<?";
+		final String[] args = {String.valueOf(timestamp)};
-		String[] whereArgs = {String.valueOf(timestamp)};
 		SQLiteDatabase db = this.getReadableDatabase();
-		return db.delete(Message.TABLENAME,where,whereArgs) > 0;
+		db.beginTransaction();
+		db.delete("messages_index", "uuid in (select uuid from messages where timeSent<?)", args);
+		db.delete(Message.TABLENAME, "timeSent<?", args);
+		db.setTransactionSuccessful();
+		db.endTransaction();
 	}
 
 	public MamReference getLastMessageReceived(Account account) {