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create table emp
(
emp_id int,
name varchar(127),
mgr int
) with system versioning;
insert into emp values (1, 'bill', 0),
(2, 'bill', 1),
(3, 'kate', 1);
set @ts=now(6);
delete from emp;
insert into emp values (4, 'john', 1);
with ancestors as (select * from emp) select * from ancestors;
set @tmp= "with ancestors as (select * from emp) select * from ancestors";
prepare stmt from @tmp; execute stmt; drop prepare stmt;
with ancestors as (select * from emp for system_time all) select * from ancestors;
set @tmp= "with ancestors as (select * from emp for system_time all) select * from ancestors";
prepare stmt from @tmp; execute stmt; drop prepare stmt;
with recursive ancestors as (select * from emp) select * from ancestors;
set @tmp= "with recursive ancestors as (select * from emp) select * from ancestors";
prepare stmt from @tmp; execute stmt; drop prepare stmt;
select emp_id from (select emp_id from emp where row_end>'2031-1-1') as tmp;
set @tmp= "select emp_id from (select emp_id from emp where row_end>'2031-1-1') as tmp";
prepare stmt from @tmp; execute stmt; drop prepare stmt;
with recursive
ancestors
as
(
select e.emp_id, e.name, e.mgr
from emp as e
where name = 'john'
union
select ee.emp_id, ee.name, ee.mgr
from emp as ee, ancestors as a
where ee.mgr = a.emp_id
)
select * from ancestors;
set @tmp= "
with recursive
ancestors
as
(
select e.emp_id, e.name, e.mgr
from emp as e
where name = 'john'
union
select ee.emp_id, ee.name, ee.mgr
from emp as ee, ancestors as a
where ee.mgr = a.emp_id
)
select * from ancestors";
prepare stmt from @tmp; execute stmt; drop prepare stmt;
#385
with recursive
ancestors
as
(
select e.emp_id, e.name, e.mgr
from emp for system_time as of timestamp @ts as e
where name = 'bill'
union
select ee.emp_id, ee.name, ee.mgr
from emp for system_time as of timestamp @ts as ee,
ancestors as a
where ee.mgr = a.emp_id
)
select * from ancestors;
set @tmp= "
with recursive
ancestors
as
(
select e.emp_id, e.name, e.mgr
from emp for system_time as of timestamp @ts as e
where name = 'bill'
union
select ee.emp_id, ee.name, ee.mgr
from emp for system_time as of timestamp @ts as ee,
ancestors as a
where ee.mgr = a.emp_id
)
select * from ancestors";
prepare stmt from @tmp; execute stmt; drop prepare stmt;
drop table emp;
create or replace table t1 (x int) with system versioning;
create or replace table t2 (y int) with system versioning;
insert into t1 values (1);
set @t0= now(6);
delete from t1;
insert into t1 values (2);
insert into t2 values (10);
--replace_column 2 # 3 #
select * from (select *, t1.row_end, t1.row_end as endo from t1) as s0;
--replace_column 3 # 4 #
select * from (select *, t1.row_end, t2.row_start from t1, t2) as s0;
--echo # SYSTEM_TIME propagation from inner to outer
select * from (select * from t1 for system_time as of timestamp @t0, t2) as s0;
with s1 as (select * from t1 for system_time as of timestamp @t0, t2) select * from s1;
--echo # leading table selection
--replace_column 3 #
select * from (select *, t1.row_end from t2, t1 for system_time as of timestamp @t0) as s2;
--replace_column 3 #
with s3 as (select *, t1.row_end from t2, t1 for system_time as of timestamp @t0) select * from s3;
--echo ### VIEW instead of t1
set @q= concat("create view vt1 as select * from t1 for system_time as of timestamp '", @t0, "'");
prepare q from @q; execute q; drop prepare q;
create view vt2 as select * from t1;
--echo # SYSTEM_TIME propagation from view
select * from vt1;
--echo # SYSTEM_TIME propagation from inner to outer
select * from (select * from vt1, t2) as s0;
--echo ### SYSTEM_TIME clash
--error ER_VERS_NOT_VERSIONED
select * from (select * from t1 for system_time all) for system_time all as dt0;
--error ER_VERS_NOT_VERSIONED
select * from vt1 for system_time all;
--error ER_VERS_NOT_VERSIONED
with dt1 as (select * from t1 for system_time all)
select * from dt1 for system_time all;
--echo ### UNION
set @t1= now(6);
delete from t2;
insert into t2 values (3);
--echo # SYSTEM_TIME is not propagated
select x from t1 union
select y from t2;
select x from t1 for system_time as of @t0 union
select y from t2;
select x from t1 union
select y from t2 for system_time as of @t1;
select x from t1 for system_time as of @t0 union
select y from t2 for system_time as of @t1;
--echo # LEFT/RIGHT JOIN
create or replace table t1 (x int, y int) with system versioning;
create or replace table t2 (x int, y int) with system versioning;
insert into t1 values (1, 1), (1, 2), (1, 3), (4, 4), (5, 5);
insert into t2 values (1, 2), (2, 1), (3, 1);
--echo ## Outer or inner SYSTEM_TIME produces same expression
--disable_warnings
--disable_query_log
explain extended
select * from (
select t1.x, t1.y as y1, t2.x as x2, t2.y as y2
from t1 join t2 on t1.x = t2.x) for system_time as of now() as t;
let $a=`show warnings`;
--echo Query A:
echo $a;
explain extended
select * from (
select t1.x, t1.y as y1, t2.x as x2, t2.y as y2
from t1 for system_time as of now()
join t2 for system_time as of now() on t1.x = t2.x) as t;
let $b=`show warnings`;
--echo Query B:
echo $b;
if ($a == $b)
{
--echo Fine result: queries A and B are equal.
}
--enable_query_log
--enable_warnings
--echo ## LEFT JOIN: t1, t2 versioned
select * from (
select t1.x as LJ1_x1, t1.y as y1, t2.x as x2, t2.y as y2
from t1 left join t2 on t1.x = t2.x)
as derived;
alter table t2 drop system versioning;
--echo ## LEFT JOIN: t1 versioned
select * from (
select t1.x as LJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2
from t1 left join t2 on t1.x = t2.x)
as derived;
alter table t1 drop system versioning;
alter table t2 add system versioning;
--echo ## LEFT JOIN: t2 versioned
select * from (
select t1.x as LJ3_x1, t1.y as y1, t2.x as x2, t2.y as y2
from t1 left join t2 on t1.x = t2.x)
as derived;
alter table t1 add system versioning;
--echo ## RIGHT JOIN: t1, t2 versioned
select * from (
select t1.x as RJ1_x1, t1.y as y1, t2.x as x2, t2.y as y2
from t1 right join t2 on t1.x = t2.x)
as derived;
alter table t2 drop system versioning;
--echo ## RIGHT JOIN: t1 versioned
select * from (
select t1.x as RJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2
from t1 right join t2 on t1.x = t2.x)
as derived;
alter table t1 drop system versioning;
alter table t2 add system versioning;
--echo ## RIGHT JOIN: t2 versioned
select * from (
select t1.x as RJ3_x1, t1.y as y1, t2.x as x2, t2.y as y2
from t1 right join t2 on t1.x = t2.x)
as derived;
drop table t1, t2;
drop view vt1, vt2;
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