types

type Column struct {
	// Spanner column name.
	Name string
	// The spanner table this column belongs to.
	Table Table
}

type Entity struct {
	// Entity ID like "E1", "E2"
	ID string
	// The spanner table this entity belongs to.
	Table Table
}

type FuncDeps struct {
}

type InArcInfo struct {
	Table  string
	Pred   string
	SubCol string
	ObjCol string
}

type Mapping struct {
	// Predicate could be a string value or an Entity.
	Pred interface{}
	// Subject is a table entity.
	Sub Entity
	// Object indicates the column of the entity.
	Obj interface{}
}

type Node struct {
	// Alias of a node in datalog query, should start with "?".
	Alias string
}

type OutArcInfo struct {
	Pred   string
	Column string
	IsNode bool
}

type Query struct {
	// Query predicate is a string of schema.
	Pred string
	// Query subject is a node.
	Sub Node
	// Query object is a node or string.
	Obj interface{}
}

type QueryOptions struct {
	Limit    int
	Db       string
	Prov     bool
	Distinct bool
	Orderby  string
	ASC      bool
}

type Table struct {
	// Spanner table name.
	Name string
	// Id used to distinguish same table when self join.
	ID string
}