Schema of "Create table t SELECT * FROM tbl" drops default values when compared to MySql

[nicktobey]

Example repro:

CREATE TABLE source (
    v1 INT PRIMARY KEY AUTO_INCREMENT,
    v2 INT DEFAULT 1,
    v3 INT 
);
CREATE TABLE dest SELECT * FROM source;
SHOW CREATE TABLE dest;

MySql output:

Table | Create Table
dest | CREATE TABLE `dest` (   `v1` int(11) NOT NULL DEFAULT '0',   `v2` int(11) DEFAULT '1',   `v3` int(11) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8

Dolt output:

+-------+------------------------------------------------------------------+
| Table | Create Table                                                     |
+-------+------------------------------------------------------------------+
| dest  | CREATE TABLE `dest` (                                            |
|       |   `v1` int NOT NULL,                                             |
|       |   `v2` int,                                                      |
|       |   `v3` int                                                       |
|       | ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_bin |
+-------+------------------------------------------------------------------+

[nicktobey]

Note that MySql both preserves default values from the original table when present, and creates new ones when not present. We do neither.

[nicktobey]

I believe that the original default value isn't being preserved because we generate a plan that looks like this:

+------------------------------------------+
| plan                                     |
+------------------------------------------+
| TableCopier                              |
|  ├─ Source: Project                      |
|  |  ├─ Child: ResolvedTable              |
|  |  └─ Projection: StarExpression        |
|  └─ Destination: CreateTable             |
+------------------------------------------+

the CreateTable node is assigned the Schema of the Project node, but the schema of the Project node doesn't reflect the defaultness of the underlying table. (I'm not sure whether that's a bug or intended behavior.)