Improve array_agg and Array processing

The :class:`_functions.array_agg` will now set the array dimensions to 1.
Improved :class:`_types.ARRAY` processing to accept ``None`` values as
value of a multi-array.

Fixes: #7083
Change-Id: Iafec4f77fde9719ccc7c8535bf6235dbfbc62102

2 files changed, 5 insertions, 1 deletions

diff --git a/lib/sqlalchemy/sql/functions.py b/lib/sqlalchemy/sql/functions.py
index a028e7fed..c04f5fa1d 100644
--- a/lib/sqlalchemy/sql/functions.py
+++ b/lib/sqlalchemy/sql/functions.py
@@ -1407,7 +1407,9 @@ class array_agg(GenericFunction[_T]):
             if isinstance(type_from_args, sqltypes.ARRAY):
                 kwargs["type_"] = type_from_args
             else:
-                kwargs["type_"] = default_array_type(type_from_args)
+                kwargs["type_"] = default_array_type(
+                    type_from_args, dimensions=1
+                )
         kwargs["_parsed_args"] = fn_args
         super(array_agg, self).__init__(*fn_args, **kwargs)
 
diff --git a/lib/sqlalchemy/sql/sqltypes.py b/lib/sqlalchemy/sql/sqltypes.py
index fd52ec6ea..414ff03c3 100644
--- a/lib/sqlalchemy/sql/sqltypes.py
+++ b/lib/sqlalchemy/sql/sqltypes.py
@@ -3065,6 +3065,8 @@ class ARRAY(
                     dim - 1 if dim is not None else None,
                     collection_callable,
                 )
+                if x is not None
+                else None
                 for x in arr
             )