create table t1 ( pk int primary key, a int, b int, c char(10), d decimal(10, 3), e real ); insert into t1 values ( 1, 0, 1, 'one', 0.1, 0.001), ( 2, 0, 2, 'two', 0.2, 0.002), ( 3, 0, 3, 'three', 0.3, 0.003), ( 4, 1, 2, 'three', 0.4, 0.004), ( 5, 1, 1, 'two', 0.5, 0.005), ( 6, 1, 1, 'one', 0.6, 0.006), ( 7, 2, NULL, 'n_one', 0.5, 0.007), ( 8, 2, 1, 'n_two', NULL, 0.008), ( 9, 2, 2, NULL, 0.7, 0.009), (10, 2, 0, 'n_four', 0.8, 0.010), (11, 2, 10, NULL, 0.9, NULL); select pk, first_value(pk) over (order by pk), last_value(pk) over (order by pk), first_value(pk) over (order by pk desc), last_value(pk) over (order by pk desc) from t1 order by pk desc; pk first_value(pk) over (order by pk) last_value(pk) over (order by pk) first_value(pk) over (order by pk desc) last_value(pk) over (order by pk desc) 11 1 11 11 11 10 1 10 11 10 9 1 9 11 9 8 1 8 11 8 7 1 7 11 7 6 1 6 11 6 5 1 5 11 5 4 1 4 11 4 3 1 3 11 3 2 1 2 11 2 1 1 1 11 1 select pk, first_value(pk) over (order by pk RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING), last_value(pk) over (order by pk RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING), first_value(pk) over (order by pk desc RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING), last_value(pk) over (order by pk desc RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) from t1 order by pk; pk first_value(pk) over (order by pk RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) last_value(pk) over (order by pk RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) first_value(pk) over (order by pk desc RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) last_value(pk) over (order by pk desc RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) 1 1 11 11 1 2 1 11 11 1 3 1 11 11 1 4 1 11 11 1 5 1 11 11 1 6 1 11 11 1 7 1 11 11 1 8 1 11 11 1 9 1 11 11 1 10 1 11 11 1 11 1 11 11 1 select pk, first_value(pk) over (order by pk desc), last_value(pk) over (order by pk desc) from t1; pk first_value(pk) over (order by pk desc) last_value(pk) over (order by pk desc) 11 11 11 10 11 10 9 11 9 8 11 8 7 11 7 6 11 6 5 11 5 4 11 4 3 11 3 2 11 2 1 11 1 select pk, a, b, c, d, e, first_value(b) over (partition by a order by pk) as fst_b, last_value(b) over (partition by a order by pk) as lst_b, first_value(c) over (partition by a order by pk) as fst_c, last_value(c) over (partition by a order by pk) as lst_c, first_value(d) over (partition by a order by pk) as fst_d, last_value(d) over (partition by a order by pk) as lst_d, first_value(e) over (partition by a order by pk) as fst_e, last_value(e) over (partition by a order by pk) as lst_e from t1; pk a b c d e fst_b lst_b fst_c lst_c fst_d lst_d fst_e lst_e 1 0 1 one 0.100 0.001 1 1 one one 0.100 0.100 0.001 0.001 2 0 2 two 0.200 0.002 1 2 one two 0.100 0.200 0.001 0.002 3 0 3 three 0.300 0.003 1 3 one three 0.100 0.300 0.001 0.003 4 1 2 three 0.400 0.004 2 2 three three 0.400 0.400 0.004 0.004 5 1 1 two 0.500 0.005 2 1 three two 0.400 0.500 0.004 0.005 6 1 1 one 0.600 0.006 2 1 three one 0.400 0.600 0.004 0.006 7 2 NULL n_one 0.500 0.007 NULL NULL n_one n_one 0.500 0.500 0.007 0.007 8 2 1 n_two NULL 0.008 NULL 1 n_one n_two 0.500 NULL 0.007 0.008 9 2 2 NULL 0.700 0.009 NULL 2 n_one NULL 0.500 0.700 0.007 0.009 10 2 0 n_four 0.800 0.01 NULL 0 n_one n_four 0.500 0.800 0.007 0.01 11 2 10 NULL 0.900 NULL NULL 10 n_one NULL 0.500 0.900 0.007 NULL drop table t1; # # MDEV-11746: Wrong result upon using FIRST_VALUE with a window frame # create table t1 (i int); insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10); select i, first_value(i) OVER (order by i rows between CURRENT ROW and 1 FOLLOWING) as fst_1f, last_value(i) OVER (order by i rows between CURRENT ROW and 1 FOLLOWING) as last_1f, first_value(i) OVER (order by i rows between 1 PRECEDING AND 1 FOLLOWING) as fst_1p1f, last_value(i) OVER (order by i rows between 1 PRECEDING AND 1 FOLLOWING) as fst_1p1f, first_value(i) OVER (order by i rows between 2 PRECEDING AND 1 PRECEDING) as fst_2p1p, last_value(i) OVER (order by i rows between 2 PRECEDING AND 1 PRECEDING) as fst_2p1p, first_value(i) OVER (order by i rows between 1 FOLLOWING AND 2 FOLLOWING) as fst_1f2f, last_value(i) OVER (order by i rows between 1 FOLLOWING AND 2 FOLLOWING) as fst_1f2f from t1; i fst_1f last_1f fst_1p1f fst_1p1f fst_2p1p fst_2p1p fst_1f2f fst_1f2f 1 1 2 1 2 NULL NULL 2 3 2 2 3 1 3 1 1 3 4 3 3 4 2 4 1 2 4 5 4 4 5 3 5 2 3 5 6 5 5 6 4 6 3 4 6 7 6 6 7 5 7 4 5 7 8 7 7 8 6 8 5 6 8 9 8 8 9 7 9 6 7 9 10 9 9 10 8 10 7 8 10 10 10 10 10 9 10 8 9 NULL NULL drop table t1; # # MDEV-12861 FIRST_VALUE() does not preserve the exact data type # CREATE TABLE t1 (a INT, b INT, c FLOAT); INSERT INTO t1 VALUES (1,1,1),(1,2,2),(2,1,1),(2,2,2); CREATE TABLE t2 AS SELECT a, FIRST_VALUE(b) OVER(), FIRST_VALUE(c) OVER() FROM t1 GROUP BY a; SHOW CREATE TABLE t2; Table Create Table t2 CREATE TABLE `t2` ( `a` int(11) DEFAULT NULL, `FIRST_VALUE(b) OVER()` int(11) DEFAULT NULL, `FIRST_VALUE(c) OVER()` float DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 DROP TABLE t2,t1;