diff --git a/src/calibre/library/database2.py b/src/calibre/library/database2.py
index 0f3a1a72fa..8fef5d36bc 100644
--- a/src/calibre/library/database2.py
+++ b/src/calibre/library/database2.py
@@ -257,11 +257,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
              'flags',
              'uuid',
              'has_cover',
-             '''(SELECT sortconcat(bl.id, authors.name || ':::' || REPLACE(authors.sort, ',','|'))
-                 FROM authors, books_authors_link as bl
-                 WHERE bl.book=books.id and authors.id=bl.author
-                 ORDER BY bl.id) au_map''',
-             '(SELECT group_concat(format) FROM data WHERE book=books.id) formats'
+            ('au_map', 'authors', 'author', 'aum_sortconcat(link.id, authors.name, authors.sort)')
             ]
         lines = []
         for col in columns:
@@ -278,10 +274,9 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
 
         self.FIELD_MAP = {'id':0, 'title':1, 'authors':2, 'timestamp':3,
              'size':4, 'rating':5, 'tags':6, 'comments':7, 'series':8,
-             'publisher':9, 'series_index':10,
-             'sort':11, 'author_sort':12, 'formats':13, 'isbn':14, 'path':15,
-             'lccn':16, 'pubdate':17, 'flags':18, 'uuid':19, 'cover':20,
-             'au_map':21, 'formats':22}
+             'publisher':9, 'series_index':10, 'sort':11, 'author_sort':12,
+             'formats':13, 'isbn':14, 'path':15, 'lccn':16, 'pubdate':17,
+             'flags':18, 'uuid':19, 'cover':20, 'au_map':21}
 
         for k,v in self.FIELD_MAP.iteritems():
             self.field_metadata.set_field_record_index(k, v, prefer_custom=False)
@@ -710,7 +705,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         self.data.set(idx, fm['all_metadata'], mi, row_is_id = index_is_id)
 
         aut_list = row[fm['au_map']]
-        aut_list = [p.split(':::') for p in aut_list.split(',')]
+        aut_list = [p.split(':::') for p in aut_list.split(':#:')]
         aum = []
         aus = {}
         for (author, author_sort) in aut_list:
diff --git a/src/calibre/library/sqlite.py b/src/calibre/library/sqlite.py
index 0458ada27b..75856dd0f6 100644
--- a/src/calibre/library/sqlite.py
+++ b/src/calibre/library/sqlite.py
@@ -87,6 +87,23 @@ class SortedConcatenate(object):
 class SafeSortedConcatenate(SortedConcatenate):
     sep = '|'
 
+class AumSortedConcatenate(object):
+    '''String concatenation aggregator for the author sort map'''
+    def __init__(self):
+        self.ans = {}
+
+    def step(self, ndx, author, sort):
+        if author is not None:
+            self.ans[ndx] = author + ':::' + sort
+
+    def finalize(self):
+        keys = self.ans.keys()
+        if len(keys) == 0:
+            return None
+        if len(keys) == 1:
+            return self.ans[keys[0]]
+        return ':#:'.join([self.ans[v] for v in sorted(keys)])
+
 class Connection(sqlite.Connection):
 
     def get(self, *args, **kw):
@@ -155,6 +172,7 @@ class DBThread(Thread):
         c_ext_loaded = load_c_extensions(self.conn)
         self.conn.row_factory = sqlite.Row if self.row_factory else  lambda cursor, row : list(row)
         self.conn.create_aggregate('concat', 1, Concatenate)
+        self.conn.create_aggregate('aum_sortconcat', 3, AumSortedConcatenate)
         if not c_ext_loaded:
             self.conn.create_aggregate('sortconcat', 2, SortedConcatenate)
             self.conn.create_aggregate('sort_concat', 2, SafeSortedConcatenate)