diff --git a/trytond/backend/sqlite/database.py b/trytond/backend/sqlite/database.py
index 809d2803f4..be0e42facb 100644
--- a/trytond/backend/sqlite/database.py
+++ b/trytond/backend/sqlite/database.py
@@ -75,19 +75,28 @@ class SQLiteExtract(Function):
 
 
 def date_trunc(_type, date):
-    if _type == 'second':
+    if not _type:
         return date
-    try:
-        tm_tuple = time.strptime(date, '%Y-%m-%d %H:%M:%S')
-    except Exception:
+    for format_ in [
+            '%Y-%m-%d %H:%M:%S.%f',
+            '%Y-%m-%d %H:%M:%S',
+            '%Y-%m-%d',
+            '%H:%M:%S',
+            ]:
+        try:
+            value = datetime.datetime.strptime(date, format_)
+        except ValueError:
+            continue
+        else:
+            break
+    else:
         return None
-    if _type == 'year':
-        return "%i-01-01 00:00:00" % tm_tuple.tm_year
-    elif _type == 'month':
-        return "%i-%02i-01 00:00:00" % (tm_tuple.tm_year, tm_tuple.tm_mon)
-    elif _type == 'day':
-        return "%i-%02i-%02i 00:00:00" % (tm_tuple.tm_year, tm_tuple.tm_mon,
-                tm_tuple.tm_mday)
+    for attribute in [
+            'microsecond', 'second', 'minute', 'hour', 'day', 'month', 'year']:
+        if _type.startswith(attribute):
+            break
+        value = value.replace(**{attribute: 0})
+    return str(value)
 
 
 def split_part(text, delimiter, count):