Nullable doesn't work when create memory table #14522
Description
Describe the bug
Nullable doesn't work when create memory table.
To Reproduce
DataFusion CLI v44.0.0
> CREATE or replace TABLE table_with_pk (
sn INT PRIMARY KEY NOT NULL,
ts TIMESTAMP WITH TIME ZONE NOT NULL,
currency VARCHAR(3) NOT NULL,
amount FLOAT
) as VALUES
(0, '2022-01-01 06:00:00Z'::timestamp, 'EUR', 30.0),
(1, '2022-01-01 08:00:00Z'::timestamp, 'EUR', 50.0),
(2, '2022-01-01 11:30:00Z'::timestamp, 'TRY', 75.0),
(3, '2022-01-02 12:00:00Z'::timestamp, 'EUR', 200.0);
0 row(s) fetched.
Elapsed 0.032 seconds.
> show columns FROM table_with_pk;
+---------------+--------------+---------------+-------------+---------------------------------------+-------------+
| table_catalog | table_schema | table_name | column_name | data_type | is_nullable |
+---------------+--------------+---------------+-------------+---------------------------------------+-------------+
| datafusion | public | table_with_pk | sn | Int32 | YES |
| datafusion | public | table_with_pk | ts | Timestamp(Nanosecond, Some("+00:00")) | YES |
| datafusion | public | table_with_pk | currency | Utf8 | YES |
| datafusion | public | table_with_pk | amount | Float32 | YES |
+---------------+--------------+---------------+-------------+---------------------------------------+-------------+
4 row(s) fetched.
Elapsed 0.015 seconds.
Expected behavior
+---------------+--------------+---------------+-------------+---------------------------------------+-------------+
| table_catalog | table_schema | table_name | column_name | data_type | is_nullable |
+---------------+--------------+---------------+-------------+---------------------------------------+-------------+
| datafusion | public | table_with_pk | sn | Int32 | NO |
| datafusion | public | table_with_pk | ts | Timestamp(Nanosecond, Some("+00:00")) | NO |
| datafusion | public | table_with_pk | currency | Utf8 | NO |
| datafusion | public | table_with_pk | amount | Float32 | YES |
+---------------+--------------+---------------+-------------+---------------------------------------+-------------+
Additional context
No response