Module sql::query_model::attribute::core

Framework for modeling and computing derived attributes for QGM graphs.

A derived attribute is a value that is associated with a specific QGM box and can be derived from a QGM graph and other derived attributes.

To implement a new attribute, define a new type to represent that attribute and implement the Attribute and AttributeKey for that type.

Note that the current implementation does not support parameterized Attribute instances, so MyAttr is OK, but MyAttr(i32) isn’t.

Structs

AsKey

Helper struct to derive a TypeMapKey from an Attribute.

Attributes

A container for derived attributes associated with a specific QGM box.

Traits

Attribute

A trait that defines the logic for deriving an attribute.

AttributeKey

A trait sets an attribute Value type.

Functions

dependency_order

Consumes a set of attributes and produces a topologically sorted version of the elements in that set based on the dependency information provided by the Attribute::requires results.

derive_dft_attributes

derive attributes for the entire model before each transform

requirements

Compute the attributes required to derive the given set of attributes that are not already in that set.

transitive_closure

Compute the transitive closure of the given set of attributes.