Feature function

Feature functions define construction of a feature. For example sum pattern, which sums column by subject in table could be described as:

SELECT subject, SUM(COLUMN) AS feature FROM TABLE GROUP BY subject;

To make the features transferable, it is a good idea to parametrize them. Following variables are automatically defined by the engine:

@table

Required: The name of the relation.

@col1, @col2

Optional: Names of the input attributes. Use either @col1 alone or together with @col2.

@id

Optional: An attribute with the entity id.

@timestamp

Optional: An attribute, which defines a time sequence.

@target

Required: An attribute with the label.

@feature

Required: The name of the attribute with the created feature.

MySQL query:

Past results: