DROP DATABASE IF EXISTS mcs151_db;
CREATE DATABASE mcs151_db;
USE mcs151_db;
CREATE TABLE t1 (a CHAR(1), b INT)ENGINE=Columnstore;
INSERT INTO t1 VALUES ('', NULL),('a', 123),('a', 1),('b', 123),('c', 1861),('c', 1991),('d', 10701),('d', 1071),('a', 92);
SELECT a, b, AVG(b) OVER(ORDER BY a) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	92	72.0000
a	1	72.0000
a	123	72.0000
b	123	84.7500
c	1991	698.5000
c	1861	698.5000
d	1071	1995.3750
d	10701	1995.3750
SELECT a, b, AVG(b) OVER(ORDER BY b DESC) avg FROM t1;
a	b	avg
d	10701	10701.0000
c	1991	6346.0000
c	1861	4851.0000
d	1071	3906.0000
a	123	2645.0000
b	123	2645.0000
a	92	2280.2857
a	1	1995.3750
NULL	NULL	1995.3750
SELECT a, b, AVG(b) OVER w avg FROM t1 WINDOW w AS (ORDER BY a DESC);
a	b	avg
d	10701	5886.0000
d	1071	5886.0000
c	1861	3906.0000
c	1991	3906.0000
b	123	3149.4000
a	92	1995.3750
a	123	1995.3750
a	1	1995.3750
NULL	NULL	1995.3750
SELECT a, b, AVG(b) OVER w avg FROM t1 WINDOW w AS (ORDER BY b);
a	b	avg
NULL	NULL	NULL
a	1	1.0000
a	92	46.5000
b	123	84.7500
a	123	84.7500
d	1071	282.0000
c	1861	545.1667
c	1991	751.7143
d	10701	1995.3750
SELECT a, b, AVG(b) OVER(PARTITION BY a) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	92	72.0000
a	1	72.0000
a	123	72.0000
b	123	123.0000
c	1991	1926.0000
c	1861	1926.0000
d	1071	5886.0000
d	10701	5886.0000
SELECT a, b, AVG(b) OVER(PARTITION BY b) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	1	1.0000
a	92	92.0000
b	123	123.0000
a	123	123.0000
d	1071	1071.0000
c	1861	1861.0000
c	1991	1991.0000
d	10701	10701.0000
SELECT a, b, AVG(b) OVER(PARTITION BY a ORDER BY a DESC) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	92	72.0000
a	1	72.0000
a	123	72.0000
b	123	123.0000
c	1991	1926.0000
c	1861	1926.0000
d	1071	5886.0000
d	10701	5886.0000
SELECT a, b, AVG(b) OVER(PARTITION BY a ORDER BY b DESC) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	123	123.0000
a	92	107.5000
a	1	72.0000
b	123	123.0000
c	1991	1991.0000
c	1861	1926.0000
d	10701	10701.0000
d	1071	5886.0000
SELECT a, b, AVG(b) OVER(PARTITION BY a ORDER BY b ASC) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	1	1.0000
a	92	46.5000
a	123	72.0000
b	123	123.0000
c	1861	1861.0000
c	1991	1926.0000
d	1071	1071.0000
d	10701	5886.0000
SELECT a, b, AVG(b) OVER(PARTITION BY b ORDER BY a DESC) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	1	1.0000
a	92	92.0000
b	123	123.0000
a	123	123.0000
d	1071	1071.0000
c	1861	1861.0000
c	1991	1991.0000
d	10701	10701.0000
SELECT a, b, AVG(b) OVER(PARTITION BY b ORDER BY b DESC) avg FROM t1;
a	b	avg
NULL	NULL	NULL
a	1	1.0000
a	92	92.0000
b	123	123.0000
a	123	123.0000
d	1071	1071.0000
c	1861	1861.0000
c	1991	1991.0000
d	10701	10701.0000
DROP DATABASE mcs151_db;