Schema

PuppyGraph uses schemas to structure the concepts (vertices and edges) within a graph.

Graph Concepts

Vertices

Vertices (also known as nodes) are the fundamental units of which graphs are formed. Think of them as points in a space where each point can represent an object, a person, a place, or any abstract concept. Vertices can have properties. For example, if a vertex represents a person, its properties might include name: John Doe, age: 30, and occupation: Software Engineer.

Edges

Edges are the connections between vertices. They signify relationships or interactions between the vertices. In a simple graph, an edge might just be a line connecting two vertices.

Similar to vertices, edges can have properties. These properties can describe the nature or characteristics of the relationship. For example, if an edge represents a friendship between two people, it might have properties like since: 2010, indicating when the friendship began.

Modeling Data into Concepts

Modeling Vertices from Tables

All the rows for a specific vertex type needs to come from a single table.
Each vertex table needs to have an identifier column.

Modeling Edges from Tables

PuppyGraph uses a directional edge model, indicating a relationship from one vertex (the source) to another (the target).

All the rows for a specific edge type needs to come from a single table.
Each edge table needs to have an identifier column.
Each edge table needs to have columns corresponding to the ids of its end vertices.

JSON Representation

PuppyGraph has a JSON representation for its schemas.

VertexEdgeMappedTableSourceAttributeSchema

Field	Type	Description
`label`	string	A user-provided name for reference in edges and queries
`mappedTableSource`	MappedTableSource	Specifies how vertex maps to catalog
`attributes`	[]Attribute	Specifies additional attribute for queries.

Field	Type	Description
`label`	string	A user-provided name for reference in queries
`from`	string	The `from` vertex label
`to`	string	The `to` vertex label
`mappedTableSource`	MappedTableSource	Specifies how edge maps to catalog
`attributes`	[]Attribute	Specifies additional attribute for queries

Field	Type	Description
`catalog`	string	Catalog name matches the specified catalog schema.
`schema`	string	Schema name matches the schema inside the catalog.
`table`	string	Table name matches the table inside the catalog.
`metaFields` (Vertex)	object `{"id" :"string"}`	The vertex id fields inside the data source table. The id field must be string and unique.
`metaFields` (Edge)	object `{` `"id" :"string",` `"from":"string",` `"to" :"string"` `}`	id - The edge id fields inside the data source table. The id field must be string and unique. from, to - The from, to fields inside the data source table. The from and to field must be the id of the specified vertex.

Field	Type
`name`	string	The field name. The name must match the field name inside the data source table.
`type`	string	The data type of the attribute.

Building a Schema

The JSON form of the schema is comprehensive but verbose. To build a schema, it is recommended to use the Graph Schema Builder provided in PuppyGraph web UI.