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; 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; select pk, first_value(pk) over (order by pk desc), last_value(pk) over (order by pk desc) from t1; 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; drop table t1; --echo # --echo # MDEV-11746: Wrong result upon using FIRST_VALUE with a window frame --echo # 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; drop table t1; --echo # --echo # MDEV-12861 FIRST_VALUE() does not preserve the exact data type --echo # 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; DROP TABLE t2,t1;