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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,
lead(pk) over (order by pk),
lead(pk, 1) over (order by pk),
lead(pk, 2) over (order by pk),
lead(pk, 0) over (order by pk),
lead(pk, -1) over (order by pk),
lead(pk, -2) over (order by pk)
from t1
order by pk asc;
pk lead(pk) over (order by pk) lead(pk, 1) over (order by pk) lead(pk, 2) over (order by pk) lead(pk, 0) over (order by pk) lead(pk, -1) over (order by pk) lead(pk, -2) over (order by pk)
1 2 2 3 1 NULL NULL
2 3 3 4 2 1 NULL
3 4 4 5 3 2 1
4 5 5 6 4 3 2
5 6 6 7 5 4 3
6 7 7 8 6 5 4
7 8 8 9 7 6 5
8 9 9 10 8 7 6
9 10 10 11 9 8 7
10 11 11 NULL 10 9 8
11 NULL NULL NULL 11 10 9
select pk,
lag(pk) over (order by pk),
lag(pk, 1) over (order by pk),
lag(pk, 2) over (order by pk),
lag(pk, 0) over (order by pk),
lag(pk, -1) over (order by pk),
lag(pk, -2) over (order by pk)
from t1
order by pk asc;
pk lag(pk) over (order by pk) lag(pk, 1) over (order by pk) lag(pk, 2) over (order by pk) lag(pk, 0) over (order by pk) lag(pk, -1) over (order by pk) lag(pk, -2) over (order by pk)
1 NULL NULL NULL 1 2 3
2 1 1 NULL 2 3 4
3 2 2 1 3 4 5
4 3 3 2 4 5 6
5 4 4 3 5 6 7
6 5 5 4 6 7 8
7 6 6 5 7 8 9
8 7 7 6 8 9 10
9 8 8 7 9 10 11
10 9 9 8 10 11 NULL
11 10 10 9 11 NULL NULL
select pk, pk - 2,
lag(pk, pk - 2) over (order by pk),
lead(pk, pk - 2) over (order by pk)
from t1
order by pk asc;
pk pk - 2 lag(pk, pk - 2) over (order by pk) lead(pk, pk - 2) over (order by pk)
1 -1 2 NULL
2 0 2 2
3 1 2 4
4 2 2 6
5 3 2 8
6 4 2 10
7 5 2 NULL
8 6 2 NULL
9 7 2 NULL
10 8 2 NULL
11 9 2 NULL
select pk, pk - 2,
lag(pk, pk + 2) over (order by pk),
lead(pk, pk + 2) over (order by pk)
from t1
order by pk asc;
pk pk - 2 lag(pk, pk + 2) over (order by pk) lead(pk, pk + 2) over (order by pk)
1 -1 NULL 4
2 0 NULL 6
3 1 NULL 8
4 2 NULL 10
5 3 NULL NULL
6 4 NULL NULL
7 5 NULL NULL
8 6 NULL NULL
9 7 NULL NULL
10 8 NULL NULL
11 9 NULL NULL
select pk, a,
lead(pk) over (partition by a order by pk),
lead(pk, 1) over (partition by a order by pk),
lead(pk, 2) over (partition by a order by pk),
lead(pk, 0) over (partition by a order by pk),
lead(pk, -1) over (partition by a order by pk),
lead(pk, -2) over (partition by a order by pk)
from t1
order by pk asc;
pk a lead(pk) over (partition by a order by pk) lead(pk, 1) over (partition by a order by pk) lead(pk, 2) over (partition by a order by pk) lead(pk, 0) over (partition by a order by pk) lead(pk, -1) over (partition by a order by pk) lead(pk, -2) over (partition by a order by pk)
1 0 2 2 3 1 NULL NULL
2 0 3 3 NULL 2 1 NULL
3 0 NULL NULL NULL 3 2 1
4 1 5 5 6 4 NULL NULL
5 1 6 6 NULL 5 4 NULL
6 1 NULL NULL NULL 6 5 4
7 2 8 8 9 7 NULL NULL
8 2 9 9 10 8 7 NULL
9 2 10 10 11 9 8 7
10 2 11 11 NULL 10 9 8
11 2 NULL NULL NULL 11 10 9
select pk, a,
lag(pk) over (partition by a order by pk),
lag(pk, 1) over (partition by a order by pk),
lag(pk, 2) over (partition by a order by pk),
lag(pk, 0) over (partition by a order by pk),
lag(pk, -1) over (partition by a order by pk),
lag(pk, -2) over (partition by a order by pk)
from t1
order by pk asc;
pk a lag(pk) over (partition by a order by pk) lag(pk, 1) over (partition by a order by pk) lag(pk, 2) over (partition by a order by pk) lag(pk, 0) over (partition by a order by pk) lag(pk, -1) over (partition by a order by pk) lag(pk, -2) over (partition by a order by pk)
1 0 NULL NULL NULL 1 2 3
2 0 1 1 NULL 2 3 NULL
3 0 2 2 1 3 NULL NULL
4 1 NULL NULL NULL 4 5 6
5 1 4 4 NULL 5 6 NULL
6 1 5 5 4 6 NULL NULL
7 2 NULL NULL NULL 7 8 9
8 2 7 7 NULL 8 9 10
9 2 8 8 7 9 10 11
10 2 9 9 8 10 11 NULL
11 2 10 10 9 11 NULL NULL
select pk, a, pk - 2,
lag(pk, pk - 2) over (partition by a order by pk),
lead(pk, pk - 2) over (partition by a order by pk),
lag(pk, a - 2) over (partition by a order by pk),
lead(pk, a - 2) over (partition by a order by pk)
from t1
order by pk asc;
pk a pk - 2 lag(pk, pk - 2) over (partition by a order by pk) lead(pk, pk - 2) over (partition by a order by pk) lag(pk, a - 2) over (partition by a order by pk) lead(pk, a - 2) over (partition by a order by pk)
1 0 -1 2 NULL 3 NULL
2 0 0 2 2 NULL NULL
3 0 1 2 NULL NULL 1
4 1 2 NULL 6 5 NULL
5 1 3 NULL NULL 6 4
6 1 4 NULL NULL NULL 5
7 2 5 NULL NULL 7 7
8 2 6 NULL NULL 8 8
9 2 7 NULL NULL 9 9
10 2 8 NULL NULL 10 10
11 2 9 NULL NULL 11 11
select pk, a, pk - 2,
lag(pk, pk + 2) over (partition by a order by pk),
lead(pk, pk + 2) over (partition by a order by pk),
lag(pk, a + 2) over (partition by a order by pk),
lead(pk, a + 2) over (partition by a order by pk)
from t1
order by pk asc;
pk a pk - 2 lag(pk, pk + 2) over (partition by a order by pk) lead(pk, pk + 2) over (partition by a order by pk) lag(pk, a + 2) over (partition by a order by pk) lead(pk, a + 2) over (partition by a order by pk)
1 0 -1 NULL NULL NULL 3
2 0 0 NULL NULL NULL NULL
3 0 1 NULL NULL 1 NULL
4 1 2 NULL NULL NULL NULL
5 1 3 NULL NULL NULL NULL
6 1 4 NULL NULL NULL NULL
7 2 5 NULL NULL NULL 11
8 2 6 NULL NULL NULL NULL
9 2 7 NULL NULL NULL NULL
10 2 8 NULL NULL NULL NULL
11 2 9 NULL NULL 7 NULL
select pk, a, b, c, d, e,
lag(a) over (partition by a order by pk),
lag(b) over (partition by a order by pk),
lag(c) over (partition by a order by pk),
lag(d) over (partition by a order by pk),
lag(e) over (partition by a order by pk)
from t1
order by pk asc;
pk a b c d e lag(a) over (partition by a order by pk) lag(b) over (partition by a order by pk) lag(c) over (partition by a order by pk) lag(d) over (partition by a order by pk) lag(e) over (partition by a order by pk)
1 0 1 one 0.100 0.001 NULL NULL NULL NULL NULL
2 0 2 two 0.200 0.002 0 1 one 0.100 0.001
3 0 3 three 0.300 0.003 0 2 two 0.200 0.002
4 1 2 three 0.400 0.004 NULL NULL NULL NULL NULL
5 1 1 two 0.500 0.005 1 2 three 0.400 0.004
6 1 1 one 0.600 0.006 1 1 two 0.500 0.005
7 2 NULL n_one 0.500 0.007 NULL NULL NULL NULL NULL
8 2 1 n_two NULL 0.008 2 NULL n_one 0.500 0.007
9 2 2 NULL 0.700 0.009 2 1 n_two NULL 0.008
10 2 0 n_four 0.800 0.01 2 2 NULL 0.700 0.009
11 2 10 NULL 0.900 NULL 2 0 n_four 0.800 0.01
select pk, a, b, a+b,
lag(a + b) over (partition by a order by pk)
from t1
order by pk asc;
pk a b a+b lag(a + b) over (partition by a order by pk)
1 0 1 1 NULL
2 0 2 2 1
3 0 3 3 2
4 1 2 3 NULL
5 1 1 2 3
6 1 1 2 2
7 2 NULL NULL NULL
8 2 1 3 NULL
9 2 2 4 3
10 2 0 2 4
11 2 10 12 2
select pk, a, b, a+b,
lag(a + b) over (partition by a order by pk) + pk
from t1
order by pk asc;
pk a b a+b lag(a + b) over (partition by a order by pk) + pk
1 0 1 1 NULL
2 0 2 2 3
3 0 3 3 5
4 1 2 3 NULL
5 1 1 2 8
6 1 1 2 8
7 2 NULL NULL NULL
8 2 1 3 NULL
9 2 2 4 12
10 2 0 2 14
11 2 10 12 13
#
# MDEV-15204 - LAG function doesn't require ORDER BY in OVER clause
#
select pk,
lag(pk, 1) over ()
from t1;
ERROR HY000: No order list in window specification for 'lag'
select pk,
lead(pk, 1) over ()
from t1;
ERROR HY000: No order list in window specification for 'lead'
drop table t1;
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