Commit 6e401572 authored by Vicențiu Ciorbaru's avatar Vicențiu Ciorbaru

Clean up nth_value

Implement nth_value correctly and add a test case for it.
parent 53cf265b
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,
nth_value(pk, 1) over (order by pk),
nth_value(pk, 2) over (order by pk),
nth_value(pk, 0) over (order by pk),
nth_value(pk, -1) over (order by pk),
nth_value(pk, -2) over (order by pk)
from t1
order by pk asc;
pk nth_value(pk, 1) over (order by pk) nth_value(pk, 2) over (order by pk) nth_value(pk, 0) over (order by pk) nth_value(pk, -1) over (order by pk) nth_value(pk, -2) over (order by pk)
1 1 NULL NULL NULL NULL
2 1 2 NULL NULL NULL
3 1 2 NULL NULL NULL
4 1 2 NULL NULL NULL
5 1 2 NULL NULL NULL
6 1 2 NULL NULL NULL
7 1 2 NULL NULL NULL
8 1 2 NULL NULL NULL
9 1 2 NULL NULL NULL
10 1 2 NULL NULL NULL
11 1 2 NULL NULL NULL
select pk,
nth_value(pk, pk) over (order by pk),
nth_value(pk / 0.1, pk) over (order by pk)
from t1
order by pk asc;
pk nth_value(pk, pk) over (order by pk) nth_value(pk / 0.1, pk) over (order by pk)
1 1 10.0000
2 2 20.0000
3 3 30.0000
4 4 40.0000
5 5 50.0000
6 6 60.0000
7 7 70.0000
8 8 80.0000
9 9 90.0000
10 10 100.0000
11 11 110.0000
select pk,
a,
nth_value(pk, pk) over (partition by a order by pk),
nth_value(pk, a + 1) over (partition by a order by pk)
from t1
order by pk asc;
pk a nth_value(pk, pk) over (partition by a order by pk) nth_value(pk, a + 1) over (partition by a order by pk)
1 0 1 1
2 0 2 1
3 0 3 1
4 1 NULL NULL
5 1 NULL 5
6 1 NULL 5
7 2 NULL NULL
8 2 NULL NULL
9 2 NULL 9
10 2 NULL 9
11 2 NULL 9
select pk,
a,
nth_value(pk, 1) over (partition by a order by pk ROWS between 1 preceding and 1 following)
from t1;
pk a nth_value(pk, 1) over (partition by a order by pk ROWS between 1 preceding and 1 following)
1 0 1
2 0 1
3 0 2
4 1 4
5 1 4
6 1 5
7 2 7
8 2 7
9 2 8
10 2 9
11 2 10
select pk,
a,
nth_value(a, 1) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 2) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 3) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 4) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 5) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 6) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 7) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 8) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 9) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 10) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 11) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 12) over (order by a RANGE BETWEEN 1 preceding and 1 following)
from t1
order by pk asc;
pk a nth_value(a, 1) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 2) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 3) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 4) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 5) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 6) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 7) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 8) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 9) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 10) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 11) over (order by a RANGE BETWEEN 1 preceding and 1 following) nth_value(a, 12) over (order by a RANGE BETWEEN 1 preceding and 1 following)
1 0 0 0 0 1 1 1 NULL NULL NULL NULL NULL NULL
2 0 0 0 0 1 1 1 NULL NULL NULL NULL NULL NULL
3 0 0 0 0 1 1 1 NULL NULL NULL NULL NULL NULL
4 1 0 0 0 1 1 1 2 2 2 2 2 NULL
5 1 0 0 0 1 1 1 2 2 2 2 2 NULL
6 1 0 0 0 1 1 1 2 2 2 2 2 NULL
7 2 1 1 1 2 2 2 2 2 NULL NULL NULL NULL
8 2 1 1 1 2 2 2 2 2 NULL NULL NULL NULL
9 2 1 1 1 2 2 2 2 2 NULL NULL NULL NULL
10 2 1 1 1 2 2 2 2 2 NULL NULL NULL NULL
11 2 1 1 1 2 2 2 2 2 NULL NULL NULL NULL
drop table t1;
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,
nth_value(pk, 1) over (order by pk),
nth_value(pk, 2) over (order by pk),
nth_value(pk, 0) over (order by pk),
nth_value(pk, -1) over (order by pk),
nth_value(pk, -2) over (order by pk)
from t1
order by pk asc;
select pk,
nth_value(pk, pk) over (order by pk),
nth_value(pk / 0.1, pk) over (order by pk)
from t1
order by pk asc;
select pk,
a,
nth_value(pk, pk) over (partition by a order by pk),
nth_value(pk, a + 1) over (partition by a order by pk)
from t1
order by pk asc;
select pk,
a,
nth_value(pk, 1) over (partition by a order by pk ROWS between 1 preceding and 1 following)
from t1;
select pk,
a,
nth_value(a, 1) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 2) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 3) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 4) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 5) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 6) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 7) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 8) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 9) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 10) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 11) over (order by a RANGE BETWEEN 1 preceding and 1 following),
nth_value(a, 12) over (order by a RANGE BETWEEN 1 preceding and 1 following)
from t1
order by pk asc;
drop table t1;
......@@ -385,36 +385,11 @@ class Item_sum_last_value : public Item_sum_hybrid_simple
{ return get_item_copy<Item_sum_last_value>(thd, mem_root, this); }
};
class Item_sum_nth_value : public Item_sum_last_value
class Item_sum_nth_value : public Item_sum_hybrid_simple
{
public:
Item_sum_nth_value(THD *thd, Item *arg_expr, Item* offset_expr) :
Item_sum_last_value(thd, arg_expr) {
/* TODO(cvicentiu) This is messy. Item_args starts with 2 args by chance.
Clean this up by pulling out the common code from Item_sum_hybrid! */
arg_count= 2;
args[1]= offset_expr;
}
bool fix_fields(THD *thd, Item **ref)
{
Item *offset= args[1];
if (offset->fix_fields(thd, args))
return true;
/* Fix fields for the second argument as well. */
orig_args[1]= offset;
/* Item_sum_last_value fixes fields for first argument only. */
if (Item_sum_last_value::fix_fields(thd, ref))
return true;
return false;
}
bool add()
{
Item_sum_last_value::add();
return false;
}
Item_sum_hybrid_simple(thd, arg_expr, offset_expr) {}
enum Sumfunctype sum_func() const
{
......@@ -788,6 +763,7 @@ class Item_window_func : public Item_func_or_sum
switch (window_func()->sum_func()) {
case Item_sum::FIRST_VALUE_FUNC:
case Item_sum::LAST_VALUE_FUNC:
case Item_sum::NTH_VALUE_FUNC:
case Item_sum::LAG_FUNC:
case Item_sum::LEAD_FUNC:
return true;
......
......@@ -2205,10 +2205,14 @@ void add_special_frame_cursors(THD *thd, Cursor_manager *cursor_manager,
cursor_manager->add_cursor(bottom_bound);
cursor_manager->add_cursor(top_bound);
DBUG_ASSERT(item_sum->fixed);
Item *int_item= new (thd->mem_root) Item_int(thd, 1);
Item *offset_func= new (thd->mem_root)
Item_func_minus(thd, item_sum->get_arg(1),
int_item);
offset_func->fix_fields(thd, &offset_func);
fc= new Frame_positional_cursor(*top_bound,
*top_bound, *bottom_bound,
*item_sum->get_arg(1),
false);
*offset_func, false);
fc->add_sum_func(item_sum);
cursor_manager->add_cursor(fc);
break;
......
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