Gnowsys Schema

This is intended for developers. It attempts to outline the workings of the underlying relational database schema, and why some features are there. And why certain design decisions were made. Not yet comprehensive but this should pave the way for clarity.

Three layered architecture of GNOWSYS

Types

• Objecttype (OT)
• Relationtype (RT)
• Attributetype (AT)
• Metatype (MT)
• ProcessType (PT)
• SystemType (ST)

Tokens

• Object (O)
• Attribute (A)
• Relation (R)
• Process (P)
• System(S)

Metatypes

The following picture provides an overview of the nodetypes GNOWSYS-studio supports.

Some terms:

• Objecttype (OT)
• Relationtype (RT)
• Attributetype (AT)
• Object (O)
• Attribute (A)
• Relation (R)
• Metatype (MT)
• ProcessType (PT)
• SystemType (ST)
• Process (P)
• System(S)

Objecttype (OT)

The primary class specifier. eg. Cat, Mouse, Human. One can say it is used to denote the ‘entities’ as in the E-R diagram. There can be sub-classes of OT’s. That is to say, a Cat is a type of Animal. So the Cat is a subclass of Animal.

Required fields

• title

Attributetype (AT)

Specifies the type of attribute that can be attached to an OT.

Required fields

• title
• subjecttype to link to (any OT)

RT

Required fields

• title
• left_subjecttype (OT on the left side of the relationship)
• right_subjecttype (OT on the right side of the relationship)

Example

Cat chases Mouse. chases is the RT, Cat is the left_subjecttype

• title: chases
• left_subjecttype: Cat
• right_subjecttype: Mouse

O

Required fields

• title
• OT to which it belongs to

A

Required fields

• title
• AT

R

Required fields

• title
• RT

MT

Required fields

• title

PT

Required fields

• title

ST

Required fields

• title

P

Required fields

• title

S

Required fields

• title