1 files changed, 20 insertions, 1 deletions
diff --git a/lib/sqlalchemy/dialects/mssql/base.py b/lib/sqlalchemy/dialects/mssql/base.py
index 4a7e48ab8..e66d01a35 100644
--- a/lib/sqlalchemy/dialects/mssql/base.py
+++ b/lib/sqlalchemy/dialects/mssql/base.py
@@ -1156,7 +1156,7 @@ RESERVED_WORDS = {
 
 
 class REAL(sqltypes.REAL):
-    __visit_name__ = "REAL"
+    """the SQL Server REAL datatype."""
 
     def __init__(self, **kw):
         # REAL is a synonym for FLOAT(24) on SQL server.
@@ -1166,6 +1166,21 @@ class REAL(sqltypes.REAL):
         super().__init__(**kw)
 
 
+class DOUBLE_PRECISION(sqltypes.DOUBLE_PRECISION):
+    """the SQL Server DOUBLE PRECISION datatype.
+
+    .. versionadded:: 2.0.11
+
+    """
+
+    def __init__(self, **kw):
+        # DOUBLE PRECISION is a synonym for FLOAT(53) on SQL server.
+        # it is only accepted as the word "DOUBLE PRECISION" in DDL,
+        # the numeric precision value is not allowed to be present
+        kw.setdefault("precision", 53)
+        super().__init__(**kw)
+
+
 class TINYINT(sqltypes.Integer):
     __visit_name__ = "TINYINT"
 
@@ -1670,6 +1685,7 @@ ischema_names = {
     "varbinary": VARBINARY,
     "bit": BIT,
     "real": REAL,
+    "double precision": DOUBLE_PRECISION,
     "image": IMAGE,
     "xml": XML,
     "timestamp": TIMESTAMP,
@@ -1700,6 +1716,9 @@ class MSTypeCompiler(compiler.GenericTypeCompiler):
 
         return " ".join([c for c in (spec, collation) if c is not None])
 
+    def visit_double(self, type_, **kw):
+        return self.visit_DOUBLE_PRECISION(type_, **kw)
+
     def visit_FLOAT(self, type_, **kw):
         precision = getattr(type_, "precision", None)
         if precision is None: