CREATE TEMPORARY TABLE foof(col1 DOUBLE, col2 DOUBLE,
  col3 DOUBLE, col4 DOUBLE);

INSERT INTO foof(col1)
  VALUES(1),(2),(3),(4),(5),(6),(7),(8),(9),
         (10), (11), (12), (13), (14), (15);

UPDATE foof
  SET col2 = 2*col1, col3=rand(), col4=col3*col3;

PLOT CORRELATION
  SMALL BLUE CIRCLE
  WITH
    FRAME 30 30 430 430
SELECT
  col1, col2, col3, col4 FROM foof;