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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;
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