diff --git a/django/core/db/__init__.py b/django/core/db/__init__.py
index f0ffeebc2e..6636d4f176 100644
--- a/django/core/db/__init__.py
+++ b/django/core/db/__init__.py
@@ -36,6 +36,7 @@ get_limit_offset_sql = dbmod.get_limit_offset_sql
 get_random_function_sql = dbmod.get_random_function_sql
 get_table_list = dbmod.get_table_list
 get_relations = dbmod.get_relations
+quote_name = dbmod.quote_name
 OPERATOR_MAPPING = dbmod.OPERATOR_MAPPING
 DATA_TYPES = dbmod.DATA_TYPES
 DATA_TYPES_REVERSE = dbmod.DATA_TYPES_REVERSE
diff --git a/django/core/db/backends/ado_mssql.py b/django/core/db/backends/ado_mssql.py
index 9ea0d5456d..a673c4812e 100644
--- a/django/core/db/backends/ado_mssql.py
+++ b/django/core/db/backends/ado_mssql.py
@@ -110,6 +110,10 @@ def get_table_list(cursor):
 def get_relations(cursor, table_name):
     raise NotImplementedError
 
+def quote_name(name):
+    # TODO: Figure out how MS-SQL quotes database identifiers.
+    return name
+
 OPERATOR_MAPPING = {
     'exact': '=',
     'iexact': 'LIKE',
diff --git a/django/core/db/backends/mysql.py b/django/core/db/backends/mysql.py
index 23815a80cb..e7ede84a12 100644
--- a/django/core/db/backends/mysql.py
+++ b/django/core/db/backends/mysql.py
@@ -122,6 +122,11 @@ def get_table_list(cursor):
 def get_relations(cursor, table_name):
     raise NotImplementedError
 
+def quote_name(name):
+    if name.startswith("`") and name.endswith("`"):
+        return name # Quoting once is enough.
+    return "`%s`" % name
+
 OPERATOR_MAPPING = {
     'exact': '=',
     'iexact': 'LIKE',
diff --git a/django/core/db/backends/postgresql.py b/django/core/db/backends/postgresql.py
index c922fd42f6..a1de11e3df 100644
--- a/django/core/db/backends/postgresql.py
+++ b/django/core/db/backends/postgresql.py
@@ -116,6 +116,11 @@ def get_relations(cursor, table_name):
             continue
     return relations
 
+def quote_name(name):
+    if name.startswith('"') and name.endswith('"'):
+        return name # Quoting once is enough.
+    return '"%s"' % name
+
 # Register these custom typecasts, because Django expects dates/times to be
 # in Python's native (standard-library) datetime/time format, whereas psycopg
 # use mx.DateTime by default.
diff --git a/django/core/db/backends/sqlite3.py b/django/core/db/backends/sqlite3.py
index ea05302a61..3fde8c77e1 100644
--- a/django/core/db/backends/sqlite3.py
+++ b/django/core/db/backends/sqlite3.py
@@ -124,6 +124,11 @@ def get_table_list(cursor):
 def get_relations(cursor, table_name):
     raise NotImplementedError
 
+def quote_name(name):
+    if name.startswith('"') and name.endswith('"'):
+        return name # Quoting once is enough.
+    return '"%s"' % name
+
 # Operators and fields ########################################################
 
 OPERATOR_MAPPING = {