Fix planner's row-mark code for inheritance from a foreign table.

Commit 428b260f8 broke planning of cases where row marks are needed
(SELECT FOR UPDATE, etc) and one of the query's tables is a foreign
table that has regular table(s) as inheritance children.  We got the
reverse case right, but apparently were thinking that foreign tables
couldn't be inheritance parents.  Not so; so we need to be able to
add a CTID junk column while adding a new child, not only a wholerow
junk column.

Back-patch to v12 where the faulty code came in.

Amit Langote

Discussion: https://postgr.es/m/CA+HiwqEmo3FV1LAQ4TVyS2h1WM=kMkZUmbNuZSCnfHvMcUcPeA@mail.gmail.com
This commit is contained in:
Tom Lane 2021-06-02 14:38:14 -04:00
parent 79c50ca578
commit 889592344c
3 changed files with 126 additions and 2 deletions

View File

@ -7255,6 +7255,92 @@ select * from bar where f1 in (select f1 from foo) for share;
4 | 44
(4 rows)
-- Now check SELECT FOR UPDATE/SHARE with an inherited source table,
-- where the parent is itself a foreign table
create table loct4 (f1 int, f2 int, f3 int);
create foreign table foo2child (f3 int) inherits (foo2)
server loopback options (table_name 'loct4');
NOTICE: moving and merging column "f3" with inherited definition
DETAIL: User-specified column moved to the position of the inherited column.
explain (verbose, costs off)
select * from bar where f1 in (select f1 from foo2) for share;
QUERY PLAN
--------------------------------------------------------------------------------------
LockRows
Output: bar.f1, bar.f2, bar.ctid, foo2.*, bar.*, bar.tableoid, foo2.tableoid
-> Hash Join
Output: bar.f1, bar.f2, bar.ctid, foo2.*, bar.*, bar.tableoid, foo2.tableoid
Inner Unique: true
Hash Cond: (bar.f1 = foo2.f1)
-> Append
-> Seq Scan on public.bar bar_1
Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid
-> Foreign Scan on public.bar2 bar_2
Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE
-> Hash
Output: foo2.*, foo2.f1, foo2.tableoid
-> HashAggregate
Output: foo2.*, foo2.f1, foo2.tableoid
Group Key: foo2.f1
-> Append
-> Foreign Scan on public.foo2 foo2_1
Output: foo2_1.*, foo2_1.f1, foo2_1.tableoid
Remote SQL: SELECT f1, f2, f3 FROM public.loct1
-> Foreign Scan on public.foo2child foo2_2
Output: foo2_2.*, foo2_2.f1, foo2_2.tableoid
Remote SQL: SELECT f1, f2, f3 FROM public.loct4
(24 rows)
select * from bar where f1 in (select f1 from foo2) for share;
f1 | f2
----+----
2 | 22
4 | 44
(2 rows)
drop foreign table foo2child;
-- And with a local child relation of the foreign table parent
create table foo2child (f3 int) inherits (foo2);
NOTICE: moving and merging column "f3" with inherited definition
DETAIL: User-specified column moved to the position of the inherited column.
explain (verbose, costs off)
select * from bar where f1 in (select f1 from foo2) for share;
QUERY PLAN
-------------------------------------------------------------------------------------------------
LockRows
Output: bar.f1, bar.f2, bar.ctid, foo2.*, bar.*, bar.tableoid, foo2.ctid, foo2.tableoid
-> Hash Join
Output: bar.f1, bar.f2, bar.ctid, foo2.*, bar.*, bar.tableoid, foo2.ctid, foo2.tableoid
Inner Unique: true
Hash Cond: (bar.f1 = foo2.f1)
-> Append
-> Seq Scan on public.bar bar_1
Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid
-> Foreign Scan on public.bar2 bar_2
Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE
-> Hash
Output: foo2.*, foo2.f1, foo2.ctid, foo2.tableoid
-> HashAggregate
Output: foo2.*, foo2.f1, foo2.ctid, foo2.tableoid
Group Key: foo2.f1
-> Append
-> Foreign Scan on public.foo2 foo2_1
Output: foo2_1.*, foo2_1.f1, foo2_1.ctid, foo2_1.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-> Seq Scan on public.foo2child foo2_2
Output: foo2_2.*, foo2_2.f1, foo2_2.ctid, foo2_2.tableoid
(23 rows)
select * from bar where f1 in (select f1 from foo2) for share;
f1 | f2
----+----
2 | 22
4 | 44
(2 rows)
drop table foo2child;
-- Check UPDATE with inherited target and an inherited source table
explain (verbose, costs off)
update bar set f2 = f2 + 100 where f1 in (select f1 from foo);

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@ -1891,6 +1891,27 @@ explain (verbose, costs off)
select * from bar where f1 in (select f1 from foo) for share;
select * from bar where f1 in (select f1 from foo) for share;
-- Now check SELECT FOR UPDATE/SHARE with an inherited source table,
-- where the parent is itself a foreign table
create table loct4 (f1 int, f2 int, f3 int);
create foreign table foo2child (f3 int) inherits (foo2)
server loopback options (table_name 'loct4');
explain (verbose, costs off)
select * from bar where f1 in (select f1 from foo2) for share;
select * from bar where f1 in (select f1 from foo2) for share;
drop foreign table foo2child;
-- And with a local child relation of the foreign table parent
create table foo2child (f3 int) inherits (foo2);
explain (verbose, costs off)
select * from bar where f1 in (select f1 from foo2) for share;
select * from bar where f1 in (select f1 from foo2) for share;
drop table foo2child;
-- Check UPDATE with inherited target and an inherited source table
explain (verbose, costs off)
update bar set f2 = f2 + 100 where f1 in (select f1 from foo);

View File

@ -232,8 +232,25 @@ expand_inherited_rtentry(PlannerInfo *root, RelOptInfo *rel,
char resname[32];
List *newvars = NIL;
/* The old PlanRowMark should already have necessitated adding TID */
Assert(old_allMarkTypes & ~(1 << ROW_MARK_COPY));
/* Add TID junk Var if needed, unless we had it already */
if (new_allMarkTypes & ~(1 << ROW_MARK_COPY) &&
!(old_allMarkTypes & ~(1 << ROW_MARK_COPY)))
{
/* Need to fetch TID */
var = makeVar(oldrc->rti,
SelfItemPointerAttributeNumber,
TIDOID,
-1,
InvalidOid,
0);
snprintf(resname, sizeof(resname), "ctid%u", oldrc->rowmarkId);
tle = makeTargetEntry((Expr *) var,
list_length(root->processed_tlist) + 1,
pstrdup(resname),
true);
root->processed_tlist = lappend(root->processed_tlist, tle);
newvars = lappend(newvars, var);
}
/* Add whole-row junk Var if needed, unless we had it already */
if ((new_allMarkTypes & (1 << ROW_MARK_COPY)) &&