diff --git a/chrome/content/zotero/xpcom/data/collection.js b/chrome/content/zotero/xpcom/data/collection.js
index 06dc5f389..e4827c33a 100644
--- a/chrome/content/zotero/xpcom/data/collection.js
+++ b/chrome/content/zotero/xpcom/data/collection.js
@@ -550,9 +550,11 @@ Zotero.Collection.prototype.clone = function (includePrimary, newCollection) {
 /**
 * Deletes collection and all descendent collections (and optionally items)
 **/
-Zotero.Collection.prototype._eraseData = Zotero.Promise.coroutine(function* (deleteItems) {
+Zotero.Collection.prototype._eraseData = Zotero.Promise.coroutine(function* (env) {
 	Zotero.DB.requireTransaction();
 	
+	var includeItems = env.options.deleteItems;
+	
 	var collections = [this.id];
 	
 	var descendents = yield this.getDescendents(false, null, true);
@@ -612,7 +614,9 @@ Zotero.Collection.prototype._eraseData = Zotero.Promise.coroutine(function* (del
 	this.ObjectsClass.unload(collections);
 	//return Zotero.Collections.reloadAll();
 	
-	Zotero.Notifier.trigger('delete', 'collection', collections, notifierData);
+	if (!env.skipNotifier) {
+		Zotero.Notifier.trigger('delete', 'collection', collections, notifierData);
+	}
 });
 
 
diff --git a/chrome/content/zotero/xpcom/data/group.js b/chrome/content/zotero/xpcom/data/group.js
index 8d2fcfd6e..1b8e56f40 100644
--- a/chrome/content/zotero/xpcom/data/group.js
+++ b/chrome/content/zotero/xpcom/data/group.js
@@ -219,7 +219,7 @@ Zotero.Group.prototype.hasItem = function (item) {
 }
 
 
-Zotero.Group.prototype.save = function () {
+Zotero.Group.prototype.save = Zotero.Promise.coroutine(function* () {
 	if (!this.id) {
 		throw ("ID not set in Zotero.Group.save()");
 	}
@@ -233,14 +233,12 @@ Zotero.Group.prototype.save = function () {
 		return false;
 	}
 	
-	Zotero.DB.beginTransaction();
-	
-	var isNew = !this.exists();
-	
-	try {
+	yield Zotero.DB.executeTransaction(function* () {
+		var isNew = !this.exists();
+		
 		Zotero.debug("Saving group " + this.id);
 		
-		var columns = [
+		var sqlColumns = [
 			'groupID',
 			'libraryID',
 			'name',
@@ -249,7 +247,6 @@ Zotero.Group.prototype.save = function () {
 			'filesEditable',
 			'version'
 		];
-		var placeholders = columns.map(function () '?').join();
 		var sqlValues = [
 			this.id,
 			this.libraryID,
@@ -265,80 +262,57 @@ Zotero.Group.prototype.save = function () {
 				Zotero.Libraries.add(this.libraryID, 'group');
 			}
 			
-			var sql = "INSERT INTO groups (" + columns.join(', ') + ") "
-						+ "VALUES (" + placeholders.join(', ') + ")";
-			Zotero.DB.query(sql, sqlValues);
+			var sql = "INSERT INTO groups (" + sqlColumns.join(', ') + ") "
+						+ "VALUES (" + sqlColumns.map(() => '?').join(', ') + ")";
+			yield Zotero.DB.queryAsync(sql, sqlValues);
 		}
 		else {
-			columns.shift();
+			sqlColumns.shift();
 			sqlValues.shift();
 			
 			var sql = "UPDATE groups SET "
-				+ columns.map(function (val) val + '=?').join(', ')
+				+ sqlColumns.map(function (val) val + '=?').join(', ')
 				+ " WHERE groupID=?";
 			sqlValues.push(this.id);
-			Zotero.DB.query(sql, sqlValues);
+			yield Zotero.DB.queryAsync(sql, sqlValues);
 		}
-		
-		Zotero.DB.commitTransaction();
-	}
-	catch (e) {
-		Zotero.DB.rollbackTransaction();
-		throw (e);
-	}
+	}.bind(this));
 	
 	Zotero.Groups.register(this);
-	
 	Zotero.Notifier.trigger('add', 'group', this.id);
-}
+});
 
 
 /**
 * Deletes group and all descendant objects
 **/
 Zotero.Group.prototype.erase = Zotero.Promise.coroutine(function* () {
-	// Don't send notifications for items and other groups objects that are deleted,
-	// since we're really only removing the group from the client
-	var notifierDisabled = Zotero.Notifier.disable();
-	
 	yield Zotero.DB.executeTransaction(function* () {
+		var notifierData = {};
+		notifierData[this.id] = this.serialize(); // TODO: Replace with JSON
+		
 		var sql, ids, obj;
 		
 		// Delete items
-		sql = "SELECT itemID FROM items WHERE libraryID=?";
-		ids = yield Zotero.DB.columnQueryAsync(sql, this.libraryID);
-		yield Zotero.Items.erase(ids);
-		
-		// Delete collections
-		sql = "SELECT collectionID FROM collections WHERE libraryID=?";
-		ids = yield Zotero.DB.columnQueryAsync(sql, this.libraryID);
-		for each(var id in ids) {
-			obj = yield Zotero.Collections.getAsync(id);
-			// Subcollections might've already been deleted
-			if (obj) {
-				yield obj.erase();
+		var types = ['item', 'collection', 'search'];
+		for (let type of types) {
+			let objectsClass = Zotero.DataObjectUtilities.getObjectsClassForObjectType(type);
+			let sql = "SELECT " + objectsClass.idColumn + " FROM " + objectsClass.table
+				+ " WHERE libraryID=?";
+			ids = yield Zotero.DB.columnQueryAsync(sql, this.libraryID);
+			for (let i = 0; i < ids.length; i++) {
+				let id = ids[i];
+				let obj = yield Zotero.Items.getAsync(id, { noCache: true });
+				yield obj.erase({
+					skipNotifier: true
+				});
 			}
 		}
 		
-		// Delete creators
-		sql = "SELECT creatorID FROM creators WHERE libraryID=?";
-		ids = yield Zotero.DB.columnQueryAsync(sql, this.libraryID);
-		for (let i=0; i<ids.length; i++) {
-			obj = yield Zotero.Creators.getAsync(ids[i]);
-			yield obj.erase();
-		}
-		
-		// Delete saved searches
-		sql = "SELECT savedSearchID FROM savedSearches WHERE libraryID=?";
-		ids = yield Zotero.DB.columnQueryAsync(sql, this.libraryID);
-		if (ids) {
-			yield Zotero.Searches.erase(ids);
-		}
-		
-		// Delete tags
+		/*// Delete tags
 		sql = "SELECT tagID FROM tags WHERE libraryID=?";
 		ids = yield Zotero.DB.columnQueryAsync(sql, this.libraryID);
-		yield Zotero.Tags.erase(ids);
+		yield Zotero.Tags.erase(ids);*/
 		
 		// Delete delete log entries
 		sql = "DELETE FROM syncDeleteLog WHERE libraryID=?";
@@ -361,16 +335,9 @@ Zotero.Group.prototype.erase = Zotero.Promise.coroutine(function* () {
 		
 		yield Zotero.purgeDataObjects();
 		
-		var notifierData = {};
-		notifierData[this.id] = this.serialize();
+		Zotero.Groups.unregister(this.id);
+		Zotero.Notifier.trigger('delete', 'group', this.id, notifierData);
 	}.bind(this));
-	
-	if (notifierDisabled) {
-		Zotero.Notifier.enable();
-	}
-	
-	Zotero.Groups.unregister(this.id);
-	Zotero.Notifier.trigger('delete', 'group', this.id, notifierData);
 });
 
 
diff --git a/chrome/content/zotero/xpcom/data/groups.js b/chrome/content/zotero/xpcom/data/groups.js
index 286ef13a8..089f08aa6 100644
--- a/chrome/content/zotero/xpcom/data/groups.js
+++ b/chrome/content/zotero/xpcom/data/groups.js
@@ -97,11 +97,11 @@ Zotero.Groups = new function () {
 	}
 	
 	
-	this.unregister = function (id) {
+	this.unregister = function (groupID) {
 		var libraryID = _libraryIDsByGroupID[groupID];
 		delete _groupIDsByLibraryID[libraryID];
 		delete _libraryIDsByGroupID[groupID];
-		delete _cache[id];
+		delete _cache[groupID];
 	}
 	
 	
diff --git a/chrome/content/zotero/xpcom/data/item.js b/chrome/content/zotero/xpcom/data/item.js
index 877bc4386..c7d5e9528 100644
--- a/chrome/content/zotero/xpcom/data/item.js
+++ b/chrome/content/zotero/xpcom/data/item.js
@@ -3970,7 +3970,9 @@ Zotero.Item.prototype._erasePreCommit = Zotero.Promise.coroutine(function* (env)
 	
 	this.ObjectsClass.unload(this.id);
 	
-	Zotero.Notifier.trigger('delete', 'item', this.id, env.deletedItemNotifierData);
+	if (!env.skipNotifier) {
+		Zotero.Notifier.trigger('delete', 'item', this.id, env.deletedItemNotifierData);
+	}
 	
 	Zotero.Prefs.set('purge.items', true);
 	Zotero.Prefs.set('purge.creators', true);
diff --git a/chrome/content/zotero/xpcom/data/items.js b/chrome/content/zotero/xpcom/data/items.js
index 1a8f880d9..eae92306d 100644
--- a/chrome/content/zotero/xpcom/data/items.js
+++ b/chrome/content/zotero/xpcom/data/items.js
@@ -608,6 +608,8 @@ Zotero.Items = function() {
 	 * Purge unused data values
 	 */
 	this.purge = Zotero.Promise.coroutine(function* () {
+		Zotero.DB.requireTransaction();
+		
 		if (!Zotero.Prefs.get('purge.items')) {
 			return;
 		}
diff --git a/chrome/content/zotero/xpcom/data/relations.js b/chrome/content/zotero/xpcom/data/relations.js
index a5498b6ca..353830113 100644
--- a/chrome/content/zotero/xpcom/data/relations.js
+++ b/chrome/content/zotero/xpcom/data/relations.js
@@ -183,7 +183,7 @@ Zotero.Relations = function () {
 		var ids = yield Zotero.DB.columnQueryAsync(sql, params);
 		
 		for (let i=0; i<ids.length; i++) {
-			let relation = this.get(ids[i]);
+			let relation = yield this.getAsync(ids[i]);
 			yield relation.load();
 			yield relation.erase();
 		}
@@ -206,7 +206,7 @@ Zotero.Relations = function () {
 		var ids = yield Zotero.DB.columnQueryAsync(sql, params);
 		
 		for (let i=0; i<ids.length; i++) {
-			let relation = this.get(ids[i]);
+			let relation = yield this.getAsync(ids[i]);
 			yield relation.load();
 			yield relation.erase();
 		}
@@ -214,6 +214,8 @@ Zotero.Relations = function () {
 	
 	
 	this.purge = Zotero.Promise.coroutine(function* () {
+		Zotero.DB.requireTransaction();
+		
 		Zotero.debug("Purging relations");
 		var t = new Date;
 		var sql = "SELECT subject FROM relations WHERE predicate != ? "
@@ -221,21 +223,19 @@ Zotero.Relations = function () {
 		var uris = yield Zotero.DB.columnQueryAsync(sql, [this.deletedItemPredicate, this.deletedItemPredicate]);
 		if (uris) {
 			var prefix = Zotero.URI.defaultPrefix;
-			yield Zotero.DB.executeTransaction(function* () {
-				for each(var uri in uris) {
-					// Skip URIs that don't begin with the default prefix,
-					// since they don't correspond to local items
-					if (uri.indexOf(prefix) == -1) {
-						continue;
-					}
-					if (uri.indexOf("/items/") != -1 && !Zotero.URI.getURIItemID(uri)) {
-						yield this.eraseByURI(uri);
-					}
-					if (uri.indexOf("/collections/") != -1 && !Zotero.URI.getURICollectionID(uri)) {
-						yield this.eraseByURI(uri);
-					}
+			for each(var uri in uris) {
+				// Skip URIs that don't begin with the default prefix,
+				// since they don't correspond to local items
+				if (uri.indexOf(prefix) == -1) {
+					continue;
 				}
-			}.bind(this));
+				if (uri.indexOf("/items/") != -1 && !Zotero.URI.getURIItemID(uri)) {
+					yield this.eraseByURI(uri);
+				}
+				if (uri.indexOf("/collections/") != -1 && !Zotero.URI.getURICollectionID(uri)) {
+					yield this.eraseByURI(uri);
+				}
+			}
 			Zotero.debug("Purged relations in " + ((new Date) - t) + "ms");
 		}
 	});
diff --git a/chrome/content/zotero/xpcom/search.js b/chrome/content/zotero/xpcom/search.js
index 37eabdb80..11d51481a 100644
--- a/chrome/content/zotero/xpcom/search.js
+++ b/chrome/content/zotero/xpcom/search.js
@@ -213,7 +213,7 @@ Zotero.Search.prototype.clone = function (libraryID) {
 };
 
 
-Zotero.Search.prototype._eraseData = Zotero.Promise.coroutine(function* () {
+Zotero.Search.prototype._eraseData = Zotero.Promise.coroutine(function* (env) {
 	Zotero.DB.requireTransaction();
 	
 	var notifierData = {};
@@ -228,7 +228,9 @@ Zotero.Search.prototype._eraseData = Zotero.Promise.coroutine(function* () {
 	var sql = "DELETE FROM savedSearches WHERE savedSearchID=?";
 	yield Zotero.DB.queryAsync(sql, this.id);
 	
-	Zotero.Notifier.trigger('delete', 'search', this.id, notifierData);
+	if (!env.skipNotifier) {
+		Zotero.Notifier.trigger('delete', 'search', this.id, notifierData);
+	}
 });
 
 
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
index b3c4622a6..e7ff0b3fd 100644
--- a/chrome/content/zotero/xpcom/zotero.js
+++ b/chrome/content/zotero/xpcom/zotero.js
@@ -2052,14 +2052,21 @@ Components.utils.import("resource://gre/modules/osfile.jsm");
 	 * Clear entries that no longer exist from various tables
 	 */
 	this.purgeDataObjects = Zotero.Promise.coroutine(function* (skipStoragePurge) {
-		yield Zotero.Creators.purge();
-		yield Zotero.Tags.purge();
+		yield Zotero.DB.executeTransaction(function* () {
+			return Zotero.Creators.purge();
+		});
+		yield Zotero.DB.executeTransaction(function* () {
+			return Zotero.Tags.purge();
+		});
 		// TEMP: Disabled until we have async DB (and maybe SQLite FTS)
 		//Zotero.Fulltext.purgeUnusedWords();
-		yield Zotero.Items.purge();
+		yield Zotero.DB.executeTransaction(function* () {
+			yield Zotero.Items.purge();
+		});
 		// DEBUG: this might not need to be permanent
-		yield Zotero.Relations.purge();
-		yield Zotero.CharacterSets.purge();
+		yield Zotero.DB.executeTransaction(function* () {
+			yield Zotero.Relations.purge();
+		});
 	});