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Rework planning and execution of UPDATE and DELETE.

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This patch makes two closely related sets of changes:

1. For UPDATE, the subplan of the ModifyTable node now only delivers
the new values of the changed columns (i.e., the expressions computed
in the query's SET clause) plus row identity information such as CTID.
ModifyTable must re-fetch the original tuple to merge in the old
values of any unchanged columns.  The core advantage of this is that
the changed columns are uniform across all tables of an inherited or
partitioned target relation, whereas the other columns might not be.
A secondary advantage, when the UPDATE involves joins, is that less
data needs to pass through the plan tree.  The disadvantage of course
is an extra fetch of each tuple to be updated.  However, that seems to
be very nearly free in context; even worst-case tests don't show it to
add more than a couple percent to the total query cost.  At some point
it might be interesting to combine the re-fetch with the tuple access
that ModifyTable must do anyway to mark the old tuple dead; but that
would require a good deal of refactoring and it seems it wouldn't buy
all that much, so this patch doesn't attempt it.

2. For inherited UPDATE/DELETE, instead of generating a separate
subplan for each target relation, we now generate a single subplan
that is just exactly like a SELECT's plan, then stick ModifyTable
on top of that.  To let ModifyTable know which target relation a
given incoming row refers to, a tableoid junk column is added to
the row identity information.  This gets rid of the horrid hack
that was inheritance_planner(), eliminating O(N^2) planning cost
and memory consumption in cases where there were many unprunable
target relations.

Point 2 of course requires point 1, so that there is a uniform
definition of the non-junk columns to be returned by the subplan.
We can't insist on uniform definition of the row identity junk
columns however, if we want to keep the ability to have both
plain and foreign tables in a partitioning hierarchy.  Since
it wouldn't scale very far to have every child table have its
own row identity column, this patch includes provisions to merge
similar row identity columns into one column of the subplan result.
In particular, we can merge the whole-row Vars typically used as
row identity by FDWs into one column by pretending they are type
RECORD.  (It's still okay for the actual composite Datums to be
labeled with the table's rowtype OID, though.)

There is more that can be done to file down residual inefficiencies
in this patch, but it seems to be committable now.

FDW authors should note several API changes:

* The argument list for AddForeignUpdateTargets() has changed, and so
has the method it must use for adding junk columns to the query.  Call
add_row_identity_var() instead of manipulating the parse tree directly.
You might want to reconsider exactly what you're adding, too.

* PlanDirectModify() must now work a little harder to find the
ForeignScan plan node; if the foreign table is part of a partitioning
hierarchy then the ForeignScan might not be the direct child of
ModifyTable.  See postgres_fdw for sample code.

* To check whether a relation is a target relation, it's no
longer sufficient to compare its relid to root->parse->resultRelation.
Instead, check it against all_result_relids or leaf_result_relids,
as appropriate.

Amit Langote and Tom Lane

Discussion: https://postgr.es/m/CA+HiwqHpHdqdDn48yCEhynnniahH78rwcrv1rEX65-fsZGBOLQ@mail.gmail.com
This commit is contained in:
Tom Lane
2021-03-31 11:52:34 -04:00
parent 055fee7eb4
commit 86dc90056d
55 changed files with 2353 additions and 2199 deletions
Download Patch File Download Diff File Expand all files Collapse all files

790
src/backend/optimizer/plan/planner.c
View File

@ -129,9 +129,7 @@ typedef struct
/* Local functions */
static Node *preprocess_expression(PlannerInfo *root, Node *expr, int kind);
static void preprocess_qual_conditions(PlannerInfo *root, Node *jtnode);
static void inheritance_planner(PlannerInfo *root);
static void grouping_planner(PlannerInfo *root, bool inheritance_update,
double tuple_fraction);
static void grouping_planner(PlannerInfo *root, double tuple_fraction);
static grouping_sets_data *preprocess_grouping_sets(PlannerInfo *root);
static List *remap_to_groupclause_idx(List *groupClause, List *gsets,
int *tleref_to_colnum_map);
@ -615,15 +613,19 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
root->multiexpr_params = NIL;
root->eq_classes = NIL;
root->ec_merging_done = false;
root->all_result_relids =
parse->resultRelation ? bms_make_singleton(parse->resultRelation) : NULL;
root->leaf_result_relids = NULL; /* we'll find out leaf-ness later */
root->append_rel_list = NIL;
root->row_identity_vars = NIL;
root->rowMarks = NIL;
memset(root->upper_rels, 0, sizeof(root->upper_rels));
memset(root->upper_targets, 0, sizeof(root->upper_targets));
root->processed_tlist = NIL;
root->update_colnos = NIL;
root->grouping_map = NULL;
root->minmax_aggs = NIL;
root->qual_security_level = 0;
root->inhTargetKind = INHKIND_NONE;
root->hasPseudoConstantQuals = false;
root->hasAlternativeSubPlans = false;
root->hasRecursion = hasRecursion;
@ -743,6 +745,19 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
list_length(rte->securityQuals));
}
/*
* If we have now verified that the query target relation is
* non-inheriting, mark it as a leaf target.
*/
if (parse->resultRelation)
{
RangeTblEntry *rte = rt_fetch(parse->resultRelation, parse->rtable);
if (!rte->inh)
root->leaf_result_relids =
bms_make_singleton(parse->resultRelation);
}
/*
* Preprocess RowMark information. We need to do this after subquery
* pullup, so that all base relations are present.
@ -999,14 +1014,9 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
remove_useless_result_rtes(root);
/*
* Do the main planning. If we have an inherited target relation, that
* needs special processing, else go straight to grouping_planner.
* Do the main planning.
*/
if (parse->resultRelation &&
rt_fetch(parse->resultRelation, parse->rtable)->inh)
inheritance_planner(root);
else
grouping_planner(root, false, tuple_fraction);
grouping_planner(root, tuple_fraction);
/*
* Capture the set of outer-level param IDs we have access to, for use in
@ -1180,621 +1190,6 @@ preprocess_phv_expression(PlannerInfo *root, Expr *expr)
return (Expr *) preprocess_expression(root, (Node *) expr, EXPRKIND_PHV);
}
/*
* inheritance_planner
* Generate Paths in the case where the result relation is an
* inheritance set.
*
* We have to handle this case differently from cases where a source relation
* is an inheritance set. Source inheritance is expanded at the bottom of the
* plan tree (see allpaths.c), but target inheritance has to be expanded at
* the top. The reason is that for UPDATE, each target relation needs a
* different targetlist matching its own column set. Fortunately,
* the UPDATE/DELETE target can never be the nullable side of an outer join,
* so it's OK to generate the plan this way.
*
* Returns nothing; the useful output is in the Paths we attach to
* the (UPPERREL_FINAL, NULL) upperrel stored in *root.
*
* Note that we have not done set_cheapest() on the final rel; it's convenient
* to leave this to the caller.
*/
static void
inheritance_planner(PlannerInfo *root)
{
Query *parse = root->parse;
int top_parentRTindex = parse->resultRelation;
List *select_rtable;
List *select_appinfos;
List *child_appinfos;
List *old_child_rtis;
List *new_child_rtis;
Bitmapset *subqueryRTindexes;
Index next_subquery_rti;
int nominalRelation = -1;
Index rootRelation = 0;
List *final_rtable = NIL;
List *final_rowmarks = NIL;
List *final_appendrels = NIL;
int save_rel_array_size = 0;
RelOptInfo **save_rel_array = NULL;
AppendRelInfo **save_append_rel_array = NULL;
List *subpaths = NIL;
List *subroots = NIL;
List *resultRelations = NIL;
List *withCheckOptionLists = NIL;
List *returningLists = NIL;
List *rowMarks;
RelOptInfo *final_rel;
ListCell *lc;
ListCell *lc2;
Index rti;
RangeTblEntry *parent_rte;
Bitmapset *parent_relids;
Query **parent_parses;
/* Should only get here for UPDATE or DELETE */
Assert(parse->commandType == CMD_UPDATE ||
parse->commandType == CMD_DELETE);
/*
* We generate a modified instance of the original Query for each target
* relation, plan that, and put all the plans into a list that will be
* controlled by a single ModifyTable node. All the instances share the
* same rangetable, but each instance must have its own set of subquery
* RTEs within the finished rangetable because (1) they are likely to get
* scribbled on during planning, and (2) it's not inconceivable that
* subqueries could get planned differently in different cases. We need
* not create duplicate copies of other RTE kinds, in particular not the
* target relations, because they don't have either of those issues. Not
* having to duplicate the target relations is important because doing so
* (1) would result in a rangetable of length O(N^2) for N targets, with
* at least O(N^3) work expended here; and (2) would greatly complicate
* management of the rowMarks list.
*
* To begin with, generate a bitmapset of the relids of the subquery RTEs.
*/
subqueryRTindexes = NULL;
rti = 1;
foreach(lc, parse->rtable)
{
RangeTblEntry *rte = lfirst_node(RangeTblEntry, lc);
if (rte->rtekind == RTE_SUBQUERY)
subqueryRTindexes = bms_add_member(subqueryRTindexes, rti);
rti++;
}
/*
* If the parent RTE is a partitioned table, we should use that as the
* nominal target relation, because the RTEs added for partitioned tables
* (including the root parent) as child members of the inheritance set do
* not appear anywhere else in the plan, so the confusion explained below
* for non-partitioning inheritance cases is not possible.
*/
parent_rte = rt_fetch(top_parentRTindex, parse->rtable);
Assert(parent_rte->inh);
if (parent_rte->relkind == RELKIND_PARTITIONED_TABLE)
{
nominalRelation = top_parentRTindex;
rootRelation = top_parentRTindex;
}
/*
* Before generating the real per-child-relation plans, do a cycle of
* planning as though the query were a SELECT. The objective here is to
* find out which child relations need to be processed, using the same
* expansion and pruning logic as for a SELECT. We'll then pull out the
* RangeTblEntry-s generated for the child rels, and make use of the
* AppendRelInfo entries for them to guide the real planning. (This is
* rather inefficient; we could perhaps stop short of making a full Path
* tree. But this whole function is inefficient and slated for
* destruction, so let's not contort query_planner for that.)
*/
{
PlannerInfo *subroot;
/*
* Flat-copy the PlannerInfo to prevent modification of the original.
*/
subroot = makeNode(PlannerInfo);
memcpy(subroot, root, sizeof(PlannerInfo));
/*
* Make a deep copy of the parsetree for this planning cycle to mess
* around with, and change it to look like a SELECT. (Hack alert: the
* target RTE still has updatedCols set if this is an UPDATE, so that
* expand_partitioned_rtentry will correctly update
* subroot->partColsUpdated.)
*/
subroot->parse = copyObject(root->parse);
subroot->parse->commandType = CMD_SELECT;
subroot->parse->resultRelation = 0;
/*
* Ensure the subroot has its own copy of the original
* append_rel_list, since it'll be scribbled on. (Note that at this
* point, the list only contains AppendRelInfos for flattened UNION
* ALL subqueries.)
*/
subroot->append_rel_list = copyObject(root->append_rel_list);
/*
* Better make a private copy of the rowMarks, too.
*/
subroot->rowMarks = copyObject(root->rowMarks);
/* There shouldn't be any OJ info to translate, as yet */
Assert(subroot->join_info_list == NIL);
/* and we haven't created PlaceHolderInfos, either */
Assert(subroot->placeholder_list == NIL);
/* Generate Path(s) for accessing this result relation */
grouping_planner(subroot, true, 0.0 /* retrieve all tuples */ );
/* Extract the info we need. */
select_rtable = subroot->parse->rtable;
select_appinfos = subroot->append_rel_list;
/*
* We need to propagate partColsUpdated back, too. (The later
* planning cycles will not set this because they won't run
* expand_partitioned_rtentry for the UPDATE target.)
*/
root->partColsUpdated = subroot->partColsUpdated;
}
/*----------
* Since only one rangetable can exist in the final plan, we need to make
* sure that it contains all the RTEs needed for any child plan. This is
* complicated by the need to use separate subquery RTEs for each child.
* We arrange the final rtable as follows:
* 1. All original rtable entries (with their original RT indexes).
* 2. All the relation RTEs generated for children of the target table.
* 3. Subquery RTEs for children after the first. We need N * (K - 1)
* RT slots for this, if there are N subqueries and K child tables.
* 4. Additional RTEs generated during the child planning runs, such as
* children of inheritable RTEs other than the target table.
* We assume that each child planning run will create an identical set
* of type-4 RTEs.
*
* So the next thing to do is append the type-2 RTEs (the target table's
* children) to the original rtable. We look through select_appinfos
* to find them.
*
* To identify which AppendRelInfos are relevant as we thumb through
* select_appinfos, we need to look for both direct and indirect children
* of top_parentRTindex, so we use a bitmap of known parent relids.
* expand_inherited_rtentry() always processes a parent before any of that
* parent's children, so we should see an intermediate parent before its
* children.
*----------
*/
child_appinfos = NIL;
old_child_rtis = NIL;
new_child_rtis = NIL;
parent_relids = bms_make_singleton(top_parentRTindex);
foreach(lc, select_appinfos)
{
AppendRelInfo *appinfo = lfirst_node(AppendRelInfo, lc);
RangeTblEntry *child_rte;
/* append_rel_list contains all append rels; ignore others */
if (!bms_is_member(appinfo->parent_relid, parent_relids))
continue;
/* remember relevant AppendRelInfos for use below */
child_appinfos = lappend(child_appinfos, appinfo);
/* extract RTE for this child rel */
child_rte = rt_fetch(appinfo->child_relid, select_rtable);
/* and append it to the original rtable */
parse->rtable = lappend(parse->rtable, child_rte);
/* remember child's index in the SELECT rtable */
old_child_rtis = lappend_int(old_child_rtis, appinfo->child_relid);
/* and its new index in the final rtable */
new_child_rtis = lappend_int(new_child_rtis, list_length(parse->rtable));
/* if child is itself partitioned, update parent_relids */
if (child_rte->inh)
{
Assert(child_rte->relkind == RELKIND_PARTITIONED_TABLE);
parent_relids = bms_add_member(parent_relids, appinfo->child_relid);
}
}
/*
* It's possible that the RTIs we just assigned for the child rels in the
* final rtable are different from what they were in the SELECT query.
* Adjust the AppendRelInfos so that they will correctly map RT indexes to
* the final indexes. We can do this left-to-right since no child rel's
* final RT index could be greater than what it had in the SELECT query.
*/
forboth(lc, old_child_rtis, lc2, new_child_rtis)
{
int old_child_rti = lfirst_int(lc);
int new_child_rti = lfirst_int(lc2);
if (old_child_rti == new_child_rti)
continue; /* nothing to do */
Assert(old_child_rti > new_child_rti);
ChangeVarNodes((Node *) child_appinfos,
old_child_rti, new_child_rti, 0);
}
/*
* Now set up rangetable entries for subqueries for additional children
* (the first child will just use the original ones). These all have to
* look more or less real, or EXPLAIN will get unhappy; so we just make
* them all clones of the original subqueries.
*/
next_subquery_rti = list_length(parse->rtable) + 1;
if (subqueryRTindexes != NULL)
{
int n_children = list_length(child_appinfos);
while (n_children-- > 1)
{
int oldrti = -1;
while ((oldrti = bms_next_member(subqueryRTindexes, oldrti)) >= 0)
{
RangeTblEntry *subqrte;
subqrte = rt_fetch(oldrti, parse->rtable);
parse->rtable = lappend(parse->rtable, copyObject(subqrte));
}
}
}
/*
* The query for each child is obtained by translating the query for its
* immediate parent, since the AppendRelInfo data we have shows deltas
* between parents and children. We use the parent_parses array to
* remember the appropriate query trees. This is indexed by parent relid.
* Since the maximum number of parents is limited by the number of RTEs in
* the SELECT query, we use that number to allocate the array. An extra
* entry is needed since relids start from 1.
*/
parent_parses = (Query **) palloc0((list_length(select_rtable) + 1) *
sizeof(Query *));
parent_parses[top_parentRTindex] = parse;
/*
* And now we can get on with generating a plan for each child table.
*/
foreach(lc, child_appinfos)
{
AppendRelInfo *appinfo = lfirst_node(AppendRelInfo, lc);
Index this_subquery_rti = next_subquery_rti;
Query *parent_parse;
PlannerInfo *subroot;
RangeTblEntry *child_rte;
RelOptInfo *sub_final_rel;
Path *subpath;
/*
* expand_inherited_rtentry() always processes a parent before any of
* that parent's children, so the parent query for this relation
* should already be available.
*/
parent_parse = parent_parses[appinfo->parent_relid];
Assert(parent_parse != NULL);
/*
* We need a working copy of the PlannerInfo so that we can control
* propagation of information back to the main copy.
*/
subroot = makeNode(PlannerInfo);
memcpy(subroot, root, sizeof(PlannerInfo));
/*
* Generate modified query with this rel as target. We first apply
* adjust_appendrel_attrs, which copies the Query and changes
* references to the parent RTE to refer to the current child RTE,
* then fool around with subquery RTEs.
*/
subroot->parse = (Query *)
adjust_appendrel_attrs(subroot,
(Node *) parent_parse,
1, &appinfo);
/*
* If there are securityQuals attached to the parent, move them to the
* child rel (they've already been transformed properly for that).
*/
parent_rte = rt_fetch(appinfo->parent_relid, subroot->parse->rtable);
child_rte = rt_fetch(appinfo->child_relid, subroot->parse->rtable);
child_rte->securityQuals = parent_rte->securityQuals;
parent_rte->securityQuals = NIL;
/*
* HACK: setting this to a value other than INHKIND_NONE signals to
* relation_excluded_by_constraints() to treat the result relation as
* being an appendrel member.
*/
subroot->inhTargetKind =
(rootRelation != 0) ? INHKIND_PARTITIONED : INHKIND_INHERITED;
/*
* If this child is further partitioned, remember it as a parent.
* Since a partitioned table does not have any data, we don't need to
* create a plan for it, and we can stop processing it here. We do,
* however, need to remember its modified PlannerInfo for use when
* processing its children, since we'll update their varnos based on
* the delta from immediate parent to child, not from top to child.
*
* Note: a very non-obvious point is that we have not yet added
* duplicate subquery RTEs to the subroot's rtable. We mustn't,
* because then its children would have two sets of duplicates,
* confusing matters.
*/
if (child_rte->inh)
{
Assert(child_rte->relkind == RELKIND_PARTITIONED_TABLE);
parent_parses[appinfo->child_relid] = subroot->parse;
continue;
}
/*
* Set the nominal target relation of the ModifyTable node if not
* already done. If the target is a partitioned table, we already set
* nominalRelation to refer to the partition root, above. For
* non-partitioned inheritance cases, we'll use the first child
* relation (even if it's excluded) as the nominal target relation.
* Because of the way expand_inherited_rtentry works, that should be
* the RTE representing the parent table in its role as a simple
* member of the inheritance set.
*
* It would be logically cleaner to *always* use the inheritance
* parent RTE as the nominal relation; but that RTE is not otherwise
* referenced in the plan in the non-partitioned inheritance case.
* Instead the duplicate child RTE created by expand_inherited_rtentry
* is used elsewhere in the plan, so using the original parent RTE
* would give rise to confusing use of multiple aliases in EXPLAIN
* output for what the user will think is the "same" table. OTOH,
* it's not a problem in the partitioned inheritance case, because
* there is no duplicate RTE for the parent.
*/
if (nominalRelation < 0)
nominalRelation = appinfo->child_relid;
/*
* As above, each child plan run needs its own append_rel_list and
* rowmarks, which should start out as pristine copies of the
* originals. There can't be any references to UPDATE/DELETE target
* rels in them; but there could be subquery references, which we'll
* fix up in a moment.
*/
subroot->append_rel_list = copyObject(root->append_rel_list);
subroot->rowMarks = copyObject(root->rowMarks);
/*
* If this isn't the first child Query, adjust Vars and jointree
* entries to reference the appropriate set of subquery RTEs.
*/
if (final_rtable != NIL && subqueryRTindexes != NULL)
{
int oldrti = -1;
while ((oldrti = bms_next_member(subqueryRTindexes, oldrti)) >= 0)
{
Index newrti = next_subquery_rti++;
ChangeVarNodes((Node *) subroot->parse, oldrti, newrti, 0);
ChangeVarNodes((Node *) subroot->append_rel_list,
oldrti, newrti, 0);
ChangeVarNodes((Node *) subroot->rowMarks, oldrti, newrti, 0);
}
}
/* There shouldn't be any OJ info to translate, as yet */
Assert(subroot->join_info_list == NIL);
/* and we haven't created PlaceHolderInfos, either */
Assert(subroot->placeholder_list == NIL);
/* Generate Path(s) for accessing this result relation */
grouping_planner(subroot, true, 0.0 /* retrieve all tuples */ );
/*
* Select cheapest path in case there's more than one. We always run
* modification queries to conclusion, so we care only for the
* cheapest-total path.
*/
sub_final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
set_cheapest(sub_final_rel);
subpath = sub_final_rel->cheapest_total_path;
/*
* If this child rel was excluded by constraint exclusion, exclude it
* from the result plan.
*/
if (IS_DUMMY_REL(sub_final_rel))
continue;
/*
* If this is the first non-excluded child, its post-planning rtable
* becomes the initial contents of final_rtable; otherwise, copy its
* modified subquery RTEs into final_rtable, to ensure we have sane
* copies of those. Also save the first non-excluded child's version
* of the rowmarks list; we assume all children will end up with
* equivalent versions of that. Likewise for append_rel_list.
*/
if (final_rtable == NIL)
{
final_rtable = subroot->parse->rtable;
final_rowmarks = subroot->rowMarks;
final_appendrels = subroot->append_rel_list;
}
else
{
Assert(list_length(final_rtable) ==
list_length(subroot->parse->rtable));
if (subqueryRTindexes != NULL)
{
int oldrti = -1;
while ((oldrti = bms_next_member(subqueryRTindexes, oldrti)) >= 0)
{
Index newrti = this_subquery_rti++;
RangeTblEntry *subqrte;
ListCell *newrticell;
subqrte = rt_fetch(newrti, subroot->parse->rtable);
newrticell = list_nth_cell(final_rtable, newrti - 1);
lfirst(newrticell) = subqrte;
}
}
}
/*
* We need to collect all the RelOptInfos from all child plans into
* the main PlannerInfo, since setrefs.c will need them. We use the
* last child's simple_rel_array, so we have to propagate forward the
* RelOptInfos that were already built in previous children.
*/
Assert(subroot->simple_rel_array_size >= save_rel_array_size);
for (rti = 1; rti < save_rel_array_size; rti++)
{
RelOptInfo *brel = save_rel_array[rti];
if (brel)
subroot->simple_rel_array[rti] = brel;
}
save_rel_array_size = subroot->simple_rel_array_size;
save_rel_array = subroot->simple_rel_array;
save_append_rel_array = subroot->append_rel_array;
/*
* Make sure any initplans from this rel get into the outer list. Note
* we're effectively assuming all children generate the same
* init_plans.
*/
root->init_plans = subroot->init_plans;
/* Build list of sub-paths */
subpaths = lappend(subpaths, subpath);
/* Build list of modified subroots, too */
subroots = lappend(subroots, subroot);
/* Build list of target-relation RT indexes */
resultRelations = lappend_int(resultRelations, appinfo->child_relid);
/* Build lists of per-relation WCO and RETURNING targetlists */
if (parse->withCheckOptions)
withCheckOptionLists = lappend(withCheckOptionLists,
subroot->parse->withCheckOptions);
if (parse->returningList)
returningLists = lappend(returningLists,
subroot->parse->returningList);
Assert(!parse->onConflict);
}
/* Result path must go into outer query's FINAL upperrel */
final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
/*
* We don't currently worry about setting final_rel's consider_parallel
* flag in this case, nor about allowing FDWs or create_upper_paths_hook
* to get control here.
*/
if (subpaths == NIL)
{
/*
* We managed to exclude every child rel, so generate a dummy path
* representing the empty set. Although it's clear that no data will
* be updated or deleted, we will still need to have a ModifyTable
* node so that any statement triggers are executed. (This could be
* cleaner if we fixed nodeModifyTable.c to support zero child nodes,
* but that probably wouldn't be a net win.)
*/
Path *dummy_path;
/* tlist processing never got done, either */
root->processed_tlist = preprocess_targetlist(root);
final_rel->reltarget = create_pathtarget(root, root->processed_tlist);
/* Make a dummy path, cf set_dummy_rel_pathlist() */
dummy_path = (Path *) create_append_path(NULL, final_rel, NIL, NIL,
NIL, NULL, 0, false,
-1);
/* These lists must be nonempty to make a valid ModifyTable node */
subpaths = list_make1(dummy_path);
subroots = list_make1(root);
resultRelations = list_make1_int(parse->resultRelation);
if (parse->withCheckOptions)
withCheckOptionLists = list_make1(parse->withCheckOptions);
if (parse->returningList)
returningLists = list_make1(parse->returningList);
/* Disable tuple routing, too, just to be safe */
root->partColsUpdated = false;
}
else
{
/*
* Put back the final adjusted rtable into the original copy of the
* Query. (We mustn't do this if we found no non-excluded children,
* since we never saved an adjusted rtable at all.)
*/
parse->rtable = final_rtable;
root->simple_rel_array_size = save_rel_array_size;
root->simple_rel_array = save_rel_array;
root->append_rel_array = save_append_rel_array;
/* Must reconstruct original's simple_rte_array, too */
root->simple_rte_array = (RangeTblEntry **)
palloc0((list_length(final_rtable) + 1) * sizeof(RangeTblEntry *));
rti = 1;
foreach(lc, final_rtable)
{
RangeTblEntry *rte = lfirst_node(RangeTblEntry, lc);
root->simple_rte_array[rti++] = rte;
}
/* Put back adjusted rowmarks and appendrels, too */
root->rowMarks = final_rowmarks;
root->append_rel_list = final_appendrels;
}
/*
* If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node will
* have dealt with fetching non-locked marked rows, else we need to have
* ModifyTable do that.
*/
if (parse->rowMarks)
rowMarks = NIL;
else
rowMarks = root->rowMarks;
/* Create Path representing a ModifyTable to do the UPDATE/DELETE work */
add_path(final_rel, (Path *)
create_modifytable_path(root, final_rel,
parse->commandType,
parse->canSetTag,
nominalRelation,
rootRelation,
root->partColsUpdated,
resultRelations,
subpaths,
subroots,
withCheckOptionLists,
returningLists,
rowMarks,
NULL,
assign_special_exec_param(root)));
}
/*--------------------
* grouping_planner
* Perform planning steps related to grouping, aggregation, etc.
@ -1802,11 +1197,6 @@ inheritance_planner(PlannerInfo *root)
* This function adds all required top-level processing to the scan/join
* Path(s) produced by query_planner.
*
* If inheritance_update is true, we're being called from inheritance_planner
* and should not include a ModifyTable step in the resulting Path(s).
* (inheritance_planner will create a single ModifyTable node covering all the
* target tables.)
*
* tuple_fraction is the fraction of tuples we expect will be retrieved.
* tuple_fraction is interpreted as follows:
* 0: expect all tuples to be retrieved (normal case)
@ -1824,8 +1214,7 @@ inheritance_planner(PlannerInfo *root)
*--------------------
*/
static void
grouping_planner(PlannerInfo *root, bool inheritance_update,
double tuple_fraction)
grouping_planner(PlannerInfo *root, double tuple_fraction)
{
Query *parse = root->parse;
int64 offset_est = 0;
@ -1969,7 +1358,7 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
* that we can transfer its decoration (resnames etc) to the topmost
* tlist of the finished Plan. This is kept in processed_tlist.
*/
root->processed_tlist = preprocess_targetlist(root);
preprocess_targetlist(root);
/*
* Mark all the aggregates with resolved aggtranstypes, and detect
@ -2307,16 +1696,117 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
}
/*
* If this is an INSERT/UPDATE/DELETE, and we're not being called from
* inheritance_planner, add the ModifyTable node.
* If this is an INSERT/UPDATE/DELETE, add the ModifyTable node.
*/
if (parse->commandType != CMD_SELECT && !inheritance_update)
if (parse->commandType != CMD_SELECT)
{
Index rootRelation;
List *withCheckOptionLists;
List *returningLists;
List *resultRelations = NIL;
List *updateColnosLists = NIL;
List *withCheckOptionLists = NIL;
List *returningLists = NIL;
List *rowMarks;
if (bms_membership(root->all_result_relids) == BMS_MULTIPLE)
{
/* Inherited UPDATE/DELETE */
RelOptInfo *top_result_rel = find_base_rel(root,
parse->resultRelation);
int resultRelation = -1;
/* Add only leaf children to ModifyTable. */
while ((resultRelation = bms_next_member(root->leaf_result_relids,
resultRelation)) >= 0)
{
RelOptInfo *this_result_rel = find_base_rel(root,
resultRelation);
/*
* Also exclude any leaf rels that have turned dummy since
* being added to the list, for example, by being excluded
* by constraint exclusion.
*/
if (IS_DUMMY_REL(this_result_rel))
continue;
/* Build per-target-rel lists needed by ModifyTable */
resultRelations = lappend_int(resultRelations,
resultRelation);
if (parse->commandType == CMD_UPDATE)
{
List *update_colnos = root->update_colnos;
if (this_result_rel != top_result_rel)
update_colnos =
adjust_inherited_attnums_multilevel(root,
update_colnos,
this_result_rel->relid,
top_result_rel->relid);
updateColnosLists = lappend(updateColnosLists,
update_colnos);
}
if (parse->withCheckOptions)
{
List *withCheckOptions = parse->withCheckOptions;
if (this_result_rel != top_result_rel)
withCheckOptions = (List *)
adjust_appendrel_attrs_multilevel(root,
(Node *) withCheckOptions,
this_result_rel->relids,
top_result_rel->relids);
withCheckOptionLists = lappend(withCheckOptionLists,
withCheckOptions);
}
if (parse->returningList)
{
List *returningList = parse->returningList;
if (this_result_rel != top_result_rel)
returningList = (List *)
adjust_appendrel_attrs_multilevel(root,
(Node *) returningList,
this_result_rel->relids,
top_result_rel->relids);
returningLists = lappend(returningLists,
returningList);
}
}
if (resultRelations == NIL)
{
/*
* We managed to exclude every child rel, so generate a
* dummy one-relation plan using info for the top target
* rel (even though that may not be a leaf target).
* Although it's clear that no data will be updated or
* deleted, we still need to have a ModifyTable node so
* that any statement triggers will be executed. (This
* could be cleaner if we fixed nodeModifyTable.c to allow
* zero target relations, but that probably wouldn't be a
* net win.)
*/
resultRelations = list_make1_int(parse->resultRelation);
if (parse->commandType == CMD_UPDATE)
updateColnosLists = list_make1(root->update_colnos);
if (parse->withCheckOptions)
withCheckOptionLists = list_make1(parse->withCheckOptions);
if (parse->returningList)
returningLists = list_make1(parse->returningList);
}
}
else
{
/* Single-relation INSERT/UPDATE/DELETE. */
resultRelations = list_make1_int(parse->resultRelation);
if (parse->commandType == CMD_UPDATE)
updateColnosLists = list_make1(root->update_colnos);
if (parse->withCheckOptions)
withCheckOptionLists = list_make1(parse->withCheckOptions);
if (parse->returningList)
returningLists = list_make1(parse->returningList);
}
/*
* If target is a partition root table, we need to mark the
* ModifyTable node appropriately for that.
@ -2327,20 +1817,6 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
else
rootRelation = 0;
/*
* Set up the WITH CHECK OPTION and RETURNING lists-of-lists, if
* needed.
*/
if (parse->withCheckOptions)
withCheckOptionLists = list_make1(parse->withCheckOptions);
else
withCheckOptionLists = NIL;
if (parse->returningList)
returningLists = list_make1(parse->returningList);
else
returningLists = NIL;
/*
* If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node
* will have dealt with fetching non-locked marked rows, else we
@ -2353,14 +1829,14 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
path = (Path *)
create_modifytable_path(root, final_rel,
path,
parse->commandType,
parse->canSetTag,
parse->resultRelation,
rootRelation,
false,
list_make1_int(parse->resultRelation),
list_make1(path),
list_make1(root),
root->partColsUpdated,
resultRelations,
updateColnosLists,
withCheckOptionLists,
returningLists,
rowMarks,