CHANGES:

initdb process has been changed in an attempt to automatically pin some basic types.  type and proc currently.

Nearly all objects have an enforced RESTRICT / CASCADE except for in 'compiled' expressions.  Ie.  Views, function contents, default expressions, 


PG TODO's Completed
- Add pg_depend table
- Auto-destroy SERIAL
- Restrict dropping (in all cases) of required system types and functions (int4, setval, ...)



[-] completed
[*] yet to do
[?] does it need to be done?

- Create Type
- Create View
* Create View (on precompile set deps in source)
- Create Trigger
- Create Table (Columns on Types)
* Create Table / Column Defaults (on precompile set deps in source)
- Create Sequence (currval, nextval, setval are PINNED)
- Create Rule (always cascade)
- Create Operator
- Create Language
- Create Index
- Create Function
* Create Function (on precompile set additional deps in source)

- Create Aggregate (on precompile set additional deps)

- Drop Type (regress tested)
- Drop View
- Drop Trigger
- Drop Table
- Drop Sequence
- Drop Rule
- Drop Operator  
- Drop Language
- Drop Index
- Drop Function (regress tested)
- Drop Aggregate

- Alter Table / Primary Key
- Alter Table / unique index
* Alter Table / Default (Compiled default depends on functions / types within)
- Alter Table / Add Column
- Alter table / add column which creates toast table


- Base type dependency on array type managed by pg_depend (always cascaded)
- Table drop foreign key triggers as managed by pg_depend (always cascaded)
- Toast tables depend on relation (always cascade)
- Enable opt_behaviour for most items in gram.y
- Disallow base functionality (types, procedures, and catalogs required for operation) to be dropped ever
- Implicit drop of a SERIALs sequence (regress tested)




OTHER NOTES
-----------

DROP TYPE <complex type> should be restricted by DROP TYPE.  Ie.  DROP TYPE pg_class;

CREATE TABLE tab (col1 int4 DEFAULT nextval('seq'));
  DROP FUNCTION nextval(text) CASCADE;
    Drop the column (col1) or set the default to NULL?

Do objects depend on users (ownership)?  ie. DROP USER CASCADE to dump everything they own when they're removed?