DROP DATABASE IF EXISTS mcs198_db; CREATE DATABASE mcs198_db; USE mcs198_db; CREATE TABLE t1 (x INT, y MEDIUMINT, z CHAR(5))ENGINE=Columnstore; INSERT INTO t1 VALUES (NULL, NULL, ''),(20, 1, 'aaa'),(39, 2, 'aaa'),(48, 3, 'bbb'),(57, 4, 'bbb'),(66, 5, 'aaa'),(75, 6, 'aaa'),(84, 7, 'bbb'); SELECT REGR_INTERCEPT(y, x) FROM t1; REGR_INTERCEPT(y, x) -1.415580568720379 SELECT z, REGR_INTERCEPT(y, x) FROM t1 GROUP BY z ORDER BY z; z REGR_INTERCEPT(y, x) NULL NULL aaa -1.1792849631966351 bbb -2.3333333333333335 SELECT REGR_INTERCEPT(y) FROM t1; ERROR HY000: Can't initialize function 'regr_intercept'; regr_intercept() requires two arguments DROP DATABASE mcs198_db;