POSC Meta Model Specifications Version 2.3 |
Logical Data Model |
This holds the EXPRESS equivalent of Defined Data Type and Epicentre ndt's. Epicentre V2.0 has no types with aggregates, although this structure supports it.
- name (M, K: string(40))
- The name of the type.
- schema_def (M, K: schema_def(types))
- The schema in which this type is defined.
- fixed_length (M: boolean)
- This is TRUE (Y) if the type is of fixed length.
- source (M: source)
- The source of this type.
- type_code (M: ref_object)
- This is AGT for an aggregate type, SLT for a select type, EMT for an enumeration type, TYP for a type and EPT for an epic type.
- aggr_name (O: string(15))
- This is the name of the aggergate if this is an aggregate type, e.g. BAG, SET, LIST, ARRAY etc.
- max_card (O: integer)
- The maximum cardinality if this is an aggregate type.
- max_length (O: integer)
- The is the maximum length allowed where the type is a variable length string.
- min_card (O: integer)
- The minimum cardinality if this is an aggregate type.
- param_1 (O: string(40))
- This is the first parameter that is used in the definition of the Epicentre extended types.
For example, in a type with an underlying type of ELEMENT, param_1 would hold the representation constraint
- param_2 (O: string(40))
- This holds the second parameter used to define Epicentre extended types.
For example if this is a type with an underlying type of ELEMENT, this would hold position constraint.
- param_3 (O: string(40))
- This holds the third parameter used to define Epicentre extended types.
- param_4 (O: string(40))
- This holds the fourth parameter used to define Epicentre extended types.
- param_5 (O: string(40))
- This holds the fifth parameter used to define Epicentre extended types.
- param_6 (O: string(40))
- This holds the sixth parameter used to define Epicentre extended types.
- epic_type (O: epic_type)
- The underlying EXPRESS simple type or Epicentre extended type, as held in the construct epic_type.
Local rules:
- Uniqueness Constraint
- name, schema_def
Entity projects as table TYPE_DEF.
Referenced in Diagrams:
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