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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, row_number() over () from t1;
pk row_number() over ()
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 10
11 11
explain FORMAT=JSON select pk, row_number() over () from t1;
EXPLAIN
{
"query_block": {
"select_id": 1,
"cost": "COST_REPLACED",
"window_functions_computation": {
"sorts": [
{
"filesort": {
"sort_key": "pk"
}
}
],
"temporary_table": {
"nested_loop": [
{
"table": {
"table_name": "t1",
"access_type": "index",
"key": "PRIMARY",
"key_length": "4",
"used_key_parts": ["pk"],
"loops": 1,
"rows": 11,
"cost": "COST_REPLACED",
"filtered": 100,
"using_index": true
}
}
]
}
}
}
}
explain FORMAT=JSON select row_number() over (), pk from t1;
EXPLAIN
{
"query_block": {
"select_id": 1,
"cost": "COST_REPLACED",
"window_functions_computation": {
"sorts": [
{
"filesort": {
"sort_key": "`row_number() over ()`"
}
}
],
"temporary_table": {
"nested_loop": [
{
"table": {
"table_name": "t1",
"access_type": "index",
"key": "PRIMARY",
"key_length": "4",
"used_key_parts": ["pk"],
"loops": 1,
"rows": 11,
"cost": "COST_REPLACED",
"filtered": 100,
"using_index": true
}
}
]
}
}
}
}
select row_number() over () from (select 4) as t;
row_number() over ()
1
select min(a) over (), max(a) over (), a, row_number() over ()
from t1
where a = 0;
min(a) over () max(a) over () a row_number() over ()
0 0 0 1
0 0 0 2
0 0 0 3
select a, min(a) over (), max(a) over (), row_number() over ()
from t1
where a = 0;
a min(a) over () max(a) over () row_number() over ()
0 0 0 1
0 0 0 2
0 0 0 3
select min(a) over () + 1, max(a) over (), row_number() over ()
from t1
where a = 0;
min(a) over () + 1 max(a) over () row_number() over ()
1 0 1
1 0 2
1 0 3
select min(a) over () + a, max(a) over (), row_number() over ()
from t1
where a = 1;
min(a) over () + a max(a) over () row_number() over ()
2 1 1
2 1 2
2 1 3
select a + min(a) over (), max(a) over (), row_number() over ()
from t1
where a = 1;
a + min(a) over () max(a) over () row_number() over ()
2 1 1
2 1 2
2 1 3
select a + min(a) over () from t1 where a = 1;
a + min(a) over ()
2
2
2
create view win_view
as (select a, min(a) over () from t1 where a = 1);
select * from win_view;
a min(a) over ()
1 1
1 1
1 1
drop view win_view;
create view win_view
as (select a, max(a + 1) over () from t1 where a = 1);
select * from win_view;
a max(a + 1) over ()
1 2
1 2
1 2
drop view win_view;
drop table t1;
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