Schema
1. Resource hierarchy
(1) Resource
(1.1) Project extends Resource
(1.2) InformationResource extends Resource
It has a parent: Project
(1.2.1) Dataset extends InformationResource
It has children: set of DataTable
(1.2.2) Document extends InformationResource
(1.2.3) CodingSheet extends InformationResource
It has children: set ofCodingRule
(1.2.4) Ontology extends InformationResource
(1.3) DataTable extends Resource
It has a parent: Dataset
It has children: set of DataTableDataTableColumn
(1.4) DataTableColumn extends Resource
It has a parent: DataTable
(1.5) CodingRule is also a resource table, but it does NOT extend Resource because the id sequence is too large.
It has a parent: CodingSheet
(2) Resource terms tables, these are not managed through hibernate.
(2.1) resource_term keeps the keywords in a resource
(2.2.) resource_context_term keeps resources' context keywords
(2.3) resource_context_term_weight stores the similarity value between a resource term and a resource context term.
E.g., resource 1 is a dataset, it is associated with an ontology
Then the keywords in this dataset's metadata and content go to the "resource_term" table.
The keywords in the ontology go to the "resource_context_term" table.
The similarity between keyword pair (k1, k2) where k1 is in resource_term table, and k2 is in resource_context_term table is put into "resource_context_term_weight" table.
Note:
(1) resource_term table is used in basic/advanced search for ranking purpose, so it is very important to maintain this
(2) resource_context_term and resource_context_term_weight are only used in context-aware search.
2. Resource relationships
(1). Generally, the one to many relationships are caught by the Foreign Key relationship in the table.
1.1 InformationResource has FK project_id to reference project(id)
So, automatically, dataset, document, codingsheet and ontology inherits this project_id.
(2) The many to many relationships among resources are captured in the "resource_relationship"
2.1. One coding sheet can be used by many other resources (e.g., data table columns)
2.2. One ontology can be used by many other resources (e.g., data table columns)