Prediction Accuracy - Aster Analytics

The following SQL code calculates and displays the prediction accuracy.

DROP TABLE IF EXISTS st_predict_accuracy;

CREATE TABLE st_predict_accuracy DISTRIBUTE BY hash(pid) AS
  SELECT pid, pred_label :: INTEGER AS pred_label,species FROM     singletree_predict, iris_test WHERE id = pid;

  SELECT (SELECT COUNT(pid) FROM st_predict_accuracy
    WHERE pred_label = species)/(SELECT COUNT(pid)
    FROM st_predict_accuracy) AS prediction_accuracy;