[Sqlalchemy-tickets] Issue #3316: Default value doesn't work in SQLAlchemy + PostgreSQL (zzzeek/sqlalchemy)

[Ander U. <iss...@bi...>]

New issue 3316: Default value doesn't work in SQLAlchemy + PostgreSQL
https://bitbucket.org/zzzeek/sqlalchemy/issue/3316/default-value-doesnt-work-in-sqlalchemy

Ander Ustarroz:

I've found an unexpected behavior in SQLAlchemy. I'm using the following versions:
* SQLAlchemy (0.9.8)
* psycopg2 (2.5.4)
* PostgreSQL (9.3.5)
This is the table definition for the example:

```
#!python
from sqlalchemy import (
  MetaData,
  Column,
  Integer,
  Table,
  String,
)

metadata = Metadata()

users = Table('users', metadata,
  Column('id_user', Integer, primary_key=True, nullable=False),
  Column('name', String(20), unique=True),
  Column('age', Integer, nullable=False, default=0),
)

```
If now I try to execute a simple insert to the table just populating the **id_user** and **name**, the column **age** should be auto-generated right? Lets see...

```
#!python
data = {'id_user':1, 'name':'Jimmy' }
stmt = users.insert().values(data)
```

This is the resulting statement:

```
#!sql
INSERT INTO users (id_user, name, age) VALUES (1, 'Jimmy', null);
```
But the **age** column was not provided,  where is that null coming from? I was expecting this:
```
#!sql
INSERT INTO users (id_user, name) VALUES (1, 'Jimmy');
```
Or if the ***default*** flag actually works should be:
```
#!sql
INSERT INTO users (id_user, name, Age) VALUES (1, 'Jimmy', 0);
```
Could you put some light on this?