diff --git a/frappe/core/doctype/version/version.json b/frappe/core/doctype/version/version.json
index 37294355ee..57cd54b6d2 100644
--- a/frappe/core/doctype/version/version.json
+++ b/frappe/core/doctype/version/version.json
@@ -188,7 +188,7 @@
  "issingle": 0, 
  "istable": 0, 
  "max_attachments": 0, 
- "modified": "2016-12-29 14:39:45.926836", 
+ "modified": "2018-04-10 14:39:45.926836", 
  "modified_by": "Administrator", 
  "module": "Core", 
  "name": "Version", 
diff --git a/frappe/core/doctype/version/version.py b/frappe/core/doctype/version/version.py
index 671eb8c597..9d945fed11 100644
--- a/frappe/core/doctype/version/version.py
+++ b/frappe/core/doctype/version/version.py
@@ -85,4 +85,7 @@ def get_diff(old, new, for_child=False):
 		return out
 
 	else:
-		return None
\ No newline at end of file
+		return None
+
+def on_doctype_update():
+	frappe.db.add_index("Version", ["ref_doctype", "docname"])
\ No newline at end of file
diff --git a/frappe/model/db_schema.py b/frappe/model/db_schema.py
index 64d7daca71..a52538eb1d 100644
--- a/frappe/model/db_schema.py
+++ b/frappe/model/db_schema.py
@@ -110,7 +110,8 @@ class DbTable:
 
 		for col in columns:
 			if len(col.fieldname) >= 64:
-				frappe.throw(_("Fieldname is limited to 64 characters ({0})").format(frappe.bold(col.fieldname)))
+				frappe.throw(_("Fieldname is limited to 64 characters ({0})")
+					.format(frappe.bold(col.fieldname)))
 
 			if col.fieldtype in type_map and type_map[col.fieldtype][0]=="varchar":
 
@@ -119,33 +120,35 @@ class DbTable:
 				if not (1 <= new_length <= 1000):
 					frappe.throw(_("Length of {0} should be between 1 and 1000").format(col.fieldname))
 
-				try:
-					# check for truncation
-					max_length = frappe.db.sql("""select max(char_length(`{fieldname}`)) from `tab{doctype}`"""\
-						.format(fieldname=col.fieldname, doctype=self.doctype))
+				current_col = self.current_columns.get(col.fieldname, {})
+				if not current_col:
+					continue
+				current_type = self.current_columns[col.fieldname]["type"]
+				current_length = re.findall('varchar\(([\d]+)\)', current_type)
+				if not current_length:
+					# case when the field is no longer a varchar
+					continue
+				current_length = current_length[0]
+				if cint(current_length) != cint(new_length):
+					try:
+						# check for truncation
+						max_length = frappe.db.sql("""select max(char_length(`{fieldname}`)) from `tab{doctype}`"""\
+							.format(fieldname=col.fieldname, doctype=self.doctype))
 
-				except pymysql.InternalError as e:
-					if e.args[0] == ER.BAD_FIELD_ERROR:
-						# Unknown column 'column_name' in 'field list'
-						continue
+					except pymysql.InternalError as e:
+						if e.args[0] == ER.BAD_FIELD_ERROR:
+							# Unknown column 'column_name' in 'field list'
+							continue
 
-					else:
-						raise
+						else:
+							raise
 
-				if max_length and max_length[0][0] and max_length[0][0] > new_length:
-					current_type = self.current_columns[col.fieldname]["type"]
-					current_length = re.findall('varchar\(([\d]+)\)', current_type)
-					if not current_length:
-						# case when the field is no longer a varchar
-						continue
+					if max_length and max_length[0][0] and max_length[0][0] > new_length:
+						if col.fieldname in self.columns:
+							self.columns[col.fieldname].length = current_length
 
-					current_length = current_length[0]
-
-					if col.fieldname in self.columns:
-						self.columns[col.fieldname].length = current_length
-
-					frappe.msgprint(_("Reverting length to {0} for '{1}' in '{2}'; Setting the length as {3} will cause truncation of data.")\
-						.format(current_length, col.fieldname, self.doctype, new_length))
+						frappe.msgprint(_("Reverting length to {0} for '{1}' in '{2}'; Setting the length as {3} will cause truncation of data.")\
+							.format(current_length, col.fieldname, self.doctype, new_length))
 
 
 	def sync(self):
@@ -180,7 +183,8 @@ class DbTable:
 			parentfield varchar({varchar_len}),
 			parenttype varchar({varchar_len}),
 			idx int(8) not null default '0',
-			%sindex parent(parent))
+			%sindex parent(parent),
+			index modified(modified))
 			ENGINE={engine}
 			ROW_FORMAT=COMPRESSED
 			CHARACTER SET=utf8mb4