Postgres enums
==============


ERROR: when adding an enum to a table -  column "my_column" contains null values
--------------------------------------------------------------------------------

```
CREATE TYPE my_enum AS ENUM ('value1', 'value2');
ALTER TABLE some_table ADD COLUMN my_new_column my_enum NOT NULL;

ERROR:  column "my_new_column" contains null values
```

- had existing data
- new column is not null
- hack workaround - remove not-null constraint
- real fix: add a default value to the column

```
ALTER TABLE some_table ADD COLUMN my_new_column my_enum NOT NULL DEFAULT 'value1';
```
- that will take time (adds value to existing rows)
- then remove the default
```
ALTER TABLE some_table ALTER COLUMN my_new_column DROP DEFAULT;
```