opensourcemirror
/
postgresql
mirror of git://git.postgresql.org/git/postgresql.git
1
0
Fork 0
Code Issues Releases Wiki Activity
postgresql/src/backend/executor/execPartition.c

2201 lines
69 KiB
C
Raw Blame History

/*-------------------------------------------------------------------------
*
* execPartition.c
* Support routines for partitioning.
*
* Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/executor/execPartition.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/table.h"
#include "access/tableam.h"
#include "catalog/partition.h"
#include "catalog/pg_inherits.h"
#include "catalog/pg_type.h"
#include "executor/execPartition.h"
#include "executor/executor.h"
#include "foreign/fdwapi.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "partitioning/partbounds.h"
#include "partitioning/partdesc.h"
#include "partitioning/partprune.h"
#include "rewrite/rewriteManip.h"
#include "utils/acl.h"
#include "utils/lsyscache.h"
#include "utils/partcache.h"
#include "utils/rls.h"
#include "utils/ruleutils.h"
/*-----------------------
* PartitionTupleRouting - Encapsulates all information required to
* route a tuple inserted into a partitioned table to one of its leaf
* partitions.
*
* partition_root
* The partitioned table that's the target of the command.
*
* partition_dispatch_info
* Array of 'max_dispatch' elements containing a pointer to a
* PartitionDispatch object for every partitioned table touched by tuple
* routing. The entry for the target partitioned table is *always*
* present in the 0th element of this array. See comment for
* PartitionDispatchData->indexes for details on how this array is
* indexed.
*
* nonleaf_partitions
* Array of 'max_dispatch' elements containing pointers to fake
* ResultRelInfo objects for nonleaf partitions, useful for checking
* the partition constraint.
*
* num_dispatch
* The current number of items stored in the 'partition_dispatch_info'
* array. Also serves as the index of the next free array element for
* new PartitionDispatch objects that need to be stored.
*
* max_dispatch
* The current allocated size of the 'partition_dispatch_info' array.
*
* partitions
* Array of 'max_partitions' elements containing a pointer to a
* ResultRelInfo for every leaf partitions touched by tuple routing.
* Some of these are pointers to ResultRelInfos which are borrowed out of
* 'subplan_resultrel_htab'. The remainder have been built especially
* for tuple routing. See comment for PartitionDispatchData->indexes for
* details on how this array is indexed.
*
* num_partitions
* The current number of items stored in the 'partitions' array. Also
* serves as the index of the next free array element for new
* ResultRelInfo objects that need to be stored.
*
* max_partitions
* The current allocated size of the 'partitions' array.
*
* subplan_resultrel_htab
* Hash table to store subplan ResultRelInfos by Oid. This is used to
* cache ResultRelInfos from subplans of an UPDATE ModifyTable node;
* NULL in other cases. Some of these may be useful for tuple routing
* to save having to build duplicates.
*
* memcxt
* Memory context used to allocate subsidiary structs.
*-----------------------
*/
struct PartitionTupleRouting
{
Relation partition_root;
PartitionDispatch *partition_dispatch_info;
ResultRelInfo **nonleaf_partitions;
int num_dispatch;
int max_dispatch;
ResultRelInfo **partitions;
int num_partitions;
int max_partitions;
HTAB *subplan_resultrel_htab;
MemoryContext memcxt;
};
/*-----------------------
* PartitionDispatch - information about one partitioned table in a partition
* hierarchy required to route a tuple to any of its partitions. A
* PartitionDispatch is always encapsulated inside a PartitionTupleRouting
* struct and stored inside its 'partition_dispatch_info' array.
*
* reldesc
* Relation descriptor of the table
*
* key
* Partition key information of the table
*
* keystate
* Execution state required for expressions in the partition key
*
* partdesc
* Partition descriptor of the table
*
* tupslot
* A standalone TupleTableSlot initialized with this table's tuple
* descriptor, or NULL if no tuple conversion between the parent is
* required.
*
* tupmap
* TupleConversionMap to convert from the parent's rowtype to this table's
* rowtype (when extracting the partition key of a tuple just before
* routing it through this table). A NULL value is stored if no tuple
* conversion is required.
*
* indexes
* Array of partdesc->nparts elements. For leaf partitions the index
* corresponds to the partition's ResultRelInfo in the encapsulating
* PartitionTupleRouting's partitions array. For partitioned partitions,
* the index corresponds to the PartitionDispatch for it in its
* partition_dispatch_info array. -1 indicates we've not yet allocated
* anything in PartitionTupleRouting for the partition.
*-----------------------
*/
typedef struct PartitionDispatchData
{
Relation reldesc;
PartitionKey key;
List *keystate; /* list of ExprState */
PartitionDesc partdesc;
TupleTableSlot *tupslot;
AttrMap *tupmap;
int indexes[FLEXIBLE_ARRAY_MEMBER];
} PartitionDispatchData;
/* struct to hold result relations coming from UPDATE subplans */
typedef struct SubplanResultRelHashElem
{
Oid relid; /* hash key -- must be first */
ResultRelInfo *rri;
} SubplanResultRelHashElem;
static void ExecHashSubPlanResultRelsByOid(ModifyTableState *mtstate,
PartitionTupleRouting *proute);
static ResultRelInfo *ExecInitPartitionInfo(ModifyTableState *mtstate,
EState *estate, PartitionTupleRouting *proute,
PartitionDispatch dispatch,
ResultRelInfo *rootResultRelInfo,
int partidx);
static void ExecInitRoutingInfo(ModifyTableState *mtstate,
EState *estate,
PartitionTupleRouting *proute,
PartitionDispatch dispatch,
ResultRelInfo *partRelInfo,
int partidx);
static PartitionDispatch ExecInitPartitionDispatchInfo(EState *estate,
PartitionTupleRouting *proute,
Oid partoid, PartitionDispatch parent_pd, int partidx);
static void FormPartitionKeyDatum(PartitionDispatch pd,
TupleTableSlot *slot,
EState *estate,
Datum *values,
bool *isnull);
static int get_partition_for_tuple(PartitionDispatch pd, Datum *values,
bool *isnull);
static char *ExecBuildSlotPartitionKeyDescription(Relation rel,
Datum *values,
bool *isnull,
int maxfieldlen);
static List *adjust_partition_tlist(List *tlist, TupleConversionMap *map);
static void ExecInitPruningContext(PartitionPruneContext *context,
List *pruning_steps,
PartitionDesc partdesc,
PartitionKey partkey,
PlanState *planstate);
static void find_matching_subplans_recurse(PartitionPruningData *prunedata,
PartitionedRelPruningData *pprune,
bool initial_prune,
Bitmapset **validsubplans);
/*
* ExecSetupPartitionTupleRouting - sets up information needed during
* tuple routing for partitioned tables, encapsulates it in
* PartitionTupleRouting, and returns it.
*
* Callers must use the returned PartitionTupleRouting during calls to
* ExecFindPartition(). The actual ResultRelInfo for a partition is only
* allocated when the partition is found for the first time.
*
* The current memory context is used to allocate this struct and all
* subsidiary structs that will be allocated from it later on. Typically
* it should be estate->es_query_cxt.
*/
PartitionTupleRouting *
ExecSetupPartitionTupleRouting(EState *estate, ModifyTableState *mtstate,
Relation rel)
{
PartitionTupleRouting *proute;
ModifyTable *node = mtstate ? (ModifyTable *) mtstate->ps.plan : NULL;
/*
* Here we attempt to expend as little effort as possible in setting up
* the PartitionTupleRouting. Each partition's ResultRelInfo is built on
* demand, only when we actually need to route a tuple to that partition.
* The reason for this is that a common case is for INSERT to insert a
* single tuple into a partitioned table and this must be fast.
*/
proute = (PartitionTupleRouting *) palloc0(sizeof(PartitionTupleRouting));
proute->partition_root = rel;
proute->memcxt = CurrentMemoryContext;
/* Rest of members initialized by zeroing */
/*
* Initialize this table's PartitionDispatch object. Here we pass in the
* parent as NULL as we don't need to care about any parent of the target
* partitioned table.
*/
ExecInitPartitionDispatchInfo(estate, proute, RelationGetRelid(rel),
NULL, 0);
/*
* If performing an UPDATE with tuple routing, we can reuse partition
* sub-plan result rels. We build a hash table to map the OIDs of
* partitions present in mtstate->resultRelInfo to their ResultRelInfos.
* Every time a tuple is routed to a partition that we've yet to set the
* ResultRelInfo for, before we go to the trouble of making one, we check
* for a pre-made one in the hash table.
*/
if (node && node->operation == CMD_UPDATE)
ExecHashSubPlanResultRelsByOid(mtstate, proute);
return proute;
}
/*
* ExecFindPartition -- Return the ResultRelInfo for the leaf partition that
* the tuple contained in *slot should belong to.
*
* If the partition's ResultRelInfo does not yet exist in 'proute' then we set
* one up or reuse one from mtstate's resultRelInfo array. When reusing a
* ResultRelInfo from the mtstate we verify that the relation is a valid
* target for INSERTs and then set up a PartitionRoutingInfo for it.
*
* rootResultRelInfo is the relation named in the query.
*
* estate must be non-NULL; we'll need it to compute any expressions in the
* partition keys. Also, its per-tuple contexts are used as evaluation
* scratch space.
*
* If no leaf partition is found, this routine errors out with the appropriate
* error message. An error may also be raised if the found target partition
* is not a valid target for an INSERT.
*/
ResultRelInfo *
ExecFindPartition(ModifyTableState *mtstate,
ResultRelInfo *rootResultRelInfo,
PartitionTupleRouting *proute,
TupleTableSlot *slot, EState *estate)
{
PartitionDispatch *pd = proute->partition_dispatch_info;
Datum values[PARTITION_MAX_KEYS];
bool isnull[PARTITION_MAX_KEYS];
Relation rel;
PartitionDispatch dispatch;
PartitionDesc partdesc;
ExprContext *ecxt = GetPerTupleExprContext(estate);
TupleTableSlot *ecxt_scantuple_saved = ecxt->ecxt_scantuple;
TupleTableSlot *rootslot = slot;
TupleTableSlot *myslot = NULL;
MemoryContext oldcxt;
ResultRelInfo *rri = NULL;
/* use per-tuple context here to avoid leaking memory */
oldcxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
/*
* First check the root table's partition constraint, if any. No point in
* routing the tuple if it doesn't belong in the root table itself.
*/
if (rootResultRelInfo->ri_RelationDesc->rd_rel->relispartition)
ExecPartitionCheck(rootResultRelInfo, slot, estate, true);
/* start with the root partitioned table */
dispatch = pd[0];
while (dispatch != NULL)
{
int partidx = -1;
CHECK_FOR_INTERRUPTS();
rel = dispatch->reldesc;
partdesc = dispatch->partdesc;
/*
* Extract partition key from tuple. Expression evaluation machinery
* that FormPartitionKeyDatum() invokes expects ecxt_scantuple to
* point to the correct tuple slot. The slot might have changed from
* what was used for the parent table if the table of the current
* partitioning level has different tuple descriptor from the parent.
* So update ecxt_scantuple accordingly.
*/
ecxt->ecxt_scantuple = slot;
FormPartitionKeyDatum(dispatch, slot, estate, values, isnull);
/*
* If this partitioned table has no partitions or no partition for
* these values, error out.
*/
if (partdesc->nparts == 0 ||
(partidx = get_partition_for_tuple(dispatch, values, isnull)) < 0)
{
char *val_desc;
val_desc = ExecBuildSlotPartitionKeyDescription(rel,
values, isnull, 64);
Assert(OidIsValid(RelationGetRelid(rel)));
ereport(ERROR,
(errcode(ERRCODE_CHECK_VIOLATION),
errmsg("no partition of relation \"%s\" found for row",
RelationGetRelationName(rel)),
val_desc ?
errdetail("Partition key of the failing row contains %s.",
val_desc) : 0,
errtable(rel)));
}
if (partdesc->is_leaf[partidx])
{
/*
* We've reached the leaf -- hurray, we're done. Look to see if
* we've already got a ResultRelInfo for this partition.
*/
if (likely(dispatch->indexes[partidx] >= 0))
{
/* ResultRelInfo already built */
Assert(dispatch->indexes[partidx] < proute->num_partitions);
rri = proute->partitions[dispatch->indexes[partidx]];
}
else
{
bool found = false;
/*
* We have not yet set up a ResultRelInfo for this partition,
* but if we have a subplan hash table, we might have one
* there. If not, we'll have to create one.
*/
if (proute->subplan_resultrel_htab)
{
Oid partoid = partdesc->oids[partidx];
SubplanResultRelHashElem *elem;
elem = hash_search(proute->subplan_resultrel_htab,
&partoid, HASH_FIND, NULL);
if (elem)
{
found = true;
rri = elem->rri;
/* Verify this ResultRelInfo allows INSERTs */
CheckValidResultRel(rri, CMD_INSERT);
/* Set up the PartitionRoutingInfo for it */
ExecInitRoutingInfo(mtstate, estate, proute, dispatch,
rri, partidx);
}
}
/* We need to create a new one. */
if (!found)
rri = ExecInitPartitionInfo(mtstate, estate, proute,
dispatch,
rootResultRelInfo, partidx);
}
Assert(rri != NULL);
/* Signal to terminate the loop */
dispatch = NULL;
}
else
{
/*
* Partition is a sub-partitioned table; get the PartitionDispatch
*/
if (likely(dispatch->indexes[partidx] >= 0))
{
/* Already built. */
Assert(dispatch->indexes[partidx] < proute->num_dispatch);
rri = proute->nonleaf_partitions[dispatch->indexes[partidx]];
/*
* Move down to the next partition level and search again
* until we find a leaf partition that matches this tuple
*/
dispatch = pd[dispatch->indexes[partidx]];
}
else
{
/* Not yet built. Do that now. */
PartitionDispatch subdispatch;
/*
* Create the new PartitionDispatch. We pass the current one
* in as the parent PartitionDispatch
*/
subdispatch = ExecInitPartitionDispatchInfo(mtstate->ps.state,
proute,
partdesc->oids[partidx],
dispatch, partidx);
Assert(dispatch->indexes[partidx] >= 0 &&
dispatch->indexes[partidx] < proute->num_dispatch);
rri = proute->nonleaf_partitions[dispatch->indexes[partidx]];
dispatch = subdispatch;
}
/*
* Convert the tuple to the new parent's layout, if different from
* the previous parent.
*/
if (dispatch->tupslot)
{
AttrMap *map = dispatch->tupmap;
TupleTableSlot *tempslot = myslot;
myslot = dispatch->tupslot;
slot = execute_attr_map_slot(map, slot, myslot);
if (tempslot != NULL)
ExecClearTuple(tempslot);
}
}
/*
* If this partition is the default one, we must check its partition
* constraint now, which may have changed concurrently due to
* partitions being added to the parent.
*
* (We do this here, and do not rely on ExecInsert doing it, because
* we don't want to miss doing it for non-leaf partitions.)
*/
if (partidx == partdesc->boundinfo->default_index)
{
PartitionRoutingInfo *partrouteinfo = rri->ri_PartitionInfo;
/*
* The tuple must match the partition's layout for the constraint
* expression to be evaluated successfully. If the partition is
* sub-partitioned, that would already be the case due to the code
* above, but for a leaf partition the tuple still matches the
* parent's layout.
*
* Note that we have a map to convert from root to current
* partition, but not from immediate parent to current partition.
* So if we have to convert, do it from the root slot; if not, use
* the root slot as-is.
*/
if (partrouteinfo)
{
TupleConversionMap *map = partrouteinfo->pi_RootToPartitionMap;
if (map)
slot = execute_attr_map_slot(map->attrMap, rootslot,
partrouteinfo->pi_PartitionTupleSlot);
else
slot = rootslot;
}
ExecPartitionCheck(rri, slot, estate, true);
}
}
/* Release the tuple in the lowest parent's dedicated slot. */
if (myslot != NULL)
ExecClearTuple(myslot);
/* and restore ecxt's scantuple */
ecxt->ecxt_scantuple = ecxt_scantuple_saved;
MemoryContextSwitchTo(oldcxt);
return rri;
}
/*
* ExecHashSubPlanResultRelsByOid
* Build a hash table to allow fast lookups of subplan ResultRelInfos by
* partition Oid. We also populate the subplan ResultRelInfo with an
* ri_PartitionRoot.
*/
static void
ExecHashSubPlanResultRelsByOid(ModifyTableState *mtstate,
PartitionTupleRouting *proute)
{
HASHCTL ctl;
HTAB *htab;
int i;
memset(&ctl, 0, sizeof(ctl));
ctl.keysize = sizeof(Oid);
ctl.entrysize = sizeof(SubplanResultRelHashElem);
ctl.hcxt = CurrentMemoryContext;
htab = hash_create("PartitionTupleRouting table", mtstate->mt_nplans,
&ctl, HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
proute->subplan_resultrel_htab = htab;
/* Hash all subplans by their Oid */
for (i = 0; i < mtstate->mt_nplans; i++)
{
ResultRelInfo *rri = &mtstate->resultRelInfo[i];
bool found;
Oid partoid = RelationGetRelid(rri->ri_RelationDesc);
SubplanResultRelHashElem *elem;
elem = (SubplanResultRelHashElem *)
hash_search(htab, &partoid, HASH_ENTER, &found);
Assert(!found);
elem->rri = rri;
/*
* This is required in order to convert the partition's tuple to be
* compatible with the root partitioned table's tuple descriptor. When
* generating the per-subplan result rels, this was not set.
*/
rri->ri_PartitionRoot = proute->partition_root;
}
}
/*
* ExecInitPartitionInfo
* Lock the partition and initialize ResultRelInfo. Also setup other
* information for the partition and store it in the next empty slot in
* the proute->partitions array.
*
* Returns the ResultRelInfo
*/
static ResultRelInfo *
ExecInitPartitionInfo(ModifyTableState *mtstate, EState *estate,
PartitionTupleRouting *proute,
PartitionDispatch dispatch,
ResultRelInfo *rootResultRelInfo,
int partidx)
{
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
Relation rootrel = rootResultRelInfo->ri_RelationDesc,
partrel;
Relation firstResultRel = mtstate->resultRelInfo[0].ri_RelationDesc;
ResultRelInfo *leaf_part_rri;
MemoryContext oldcxt;
AttrMap *part_attmap = NULL;
bool found_whole_row;
oldcxt = MemoryContextSwitchTo(proute->memcxt);
partrel = table_open(dispatch->partdesc->oids[partidx], RowExclusiveLock);
leaf_part_rri = makeNode(ResultRelInfo);
InitResultRelInfo(leaf_part_rri,
partrel,
node ? node->rootRelation : 1,
rootrel,
estate->es_instrument);
/*
* Verify result relation is a valid target for an INSERT. An UPDATE of a
* partition-key becomes a DELETE+INSERT operation, so this check is still
* required when the operation is CMD_UPDATE.
*/
CheckValidResultRel(leaf_part_rri, CMD_INSERT);
/*
* Open partition indices. The user may have asked to check for conflicts
* within this leaf partition and do "nothing" instead of throwing an
* error. Be prepared in that case by initializing the index information
* needed by ExecInsert() to perform speculative insertions.
*/
if (partrel->rd_rel->relhasindex &&
leaf_part_rri->ri_IndexRelationDescs == NULL)
ExecOpenIndices(leaf_part_rri,
(node != NULL &&
node->onConflictAction != ONCONFLICT_NONE));
/*
* Build WITH CHECK OPTION constraints for the partition. Note that we
* didn't build the withCheckOptionList for partitions within the planner,
* but simple translation of varattnos will suffice. This only occurs for
* the INSERT case or in the case of UPDATE tuple routing where we didn't
* find a result rel to reuse in ExecSetupPartitionTupleRouting().
*/
if (node && node->withCheckOptionLists != NIL)
{
List *wcoList;
List *wcoExprs = NIL;
ListCell *ll;
int firstVarno = mtstate->resultRelInfo[0].ri_RangeTableIndex;
/*
* In the case of INSERT on a partitioned table, there is only one
* plan. Likewise, there is only one WCO list, not one per partition.
* For UPDATE, there are as many WCO lists as there are plans.
*/
Assert((node->operation == CMD_INSERT &&
list_length(node->withCheckOptionLists) == 1 &&
list_length(node->plans) == 1) ||
(node->operation == CMD_UPDATE &&
list_length(node->withCheckOptionLists) ==
list_length(node->plans)));
/*
* Use the WCO list of the first plan as a reference to calculate
* attno's for the WCO list of this partition. In the INSERT case,
* that refers to the root partitioned table, whereas in the UPDATE
* tuple routing case, that refers to the first partition in the
* mtstate->resultRelInfo array. In any case, both that relation and
* this partition should have the same columns, so we should be able
* to map attributes successfully.
*/
wcoList = linitial(node->withCheckOptionLists);
/*
* Convert Vars in it to contain this partition's attribute numbers.
*/
part_attmap =
build_attrmap_by_name(RelationGetDescr(partrel),
RelationGetDescr(firstResultRel));
wcoList = (List *)
map_variable_attnos((Node *) wcoList,
firstVarno, 0,
part_attmap,
RelationGetForm(partrel)->reltype,
&found_whole_row);
/* We ignore the value of found_whole_row. */
foreach(ll, wcoList)
{
WithCheckOption *wco = castNode(WithCheckOption, lfirst(ll));
ExprState *wcoExpr = ExecInitQual(castNode(List, wco->qual),
&mtstate->ps);
wcoExprs = lappend(wcoExprs, wcoExpr);
}
leaf_part_rri->ri_WithCheckOptions = wcoList;
leaf_part_rri->ri_WithCheckOptionExprs = wcoExprs;
}
/*
* Build the RETURNING projection for the partition. Note that we didn't
* build the returningList for partitions within the planner, but simple
* translation of varattnos will suffice. This only occurs for the INSERT
* case or in the case of UPDATE tuple routing where we didn't find a
* result rel to reuse in ExecSetupPartitionTupleRouting().
*/
if (node && node->returningLists != NIL)
{
TupleTableSlot *slot;
ExprContext *econtext;
List *returningList;
int firstVarno = mtstate->resultRelInfo[0].ri_RangeTableIndex;
/* See the comment above for WCO lists. */
Assert((node->operation == CMD_INSERT &&
list_length(node->returningLists) == 1 &&
list_length(node->plans) == 1) ||
(node->operation == CMD_UPDATE &&
list_length(node->returningLists) ==
list_length(node->plans)));
/*
* Use the RETURNING list of the first plan as a reference to
* calculate attno's for the RETURNING list of this partition. See
* the comment above for WCO lists for more details on why this is
* okay.
*/
returningList = linitial(node->returningLists);
/*
* Convert Vars in it to contain this partition's attribute numbers.
*/
if (part_attmap == NULL)
part_attmap =
build_attrmap_by_name(RelationGetDescr(partrel),
RelationGetDescr(firstResultRel));
returningList = (List *)
map_variable_attnos((Node *) returningList,
firstVarno, 0,
part_attmap,
RelationGetForm(partrel)->reltype,
&found_whole_row);
/* We ignore the value of found_whole_row. */
leaf_part_rri->ri_returningList = returningList;
/*
* Initialize the projection itself.
*
* Use the slot and the expression context that would have been set up
* in ExecInitModifyTable() for projection's output.
*/
Assert(mtstate->ps.ps_ResultTupleSlot != NULL);
slot = mtstate->ps.ps_ResultTupleSlot;
Assert(mtstate->ps.ps_ExprContext != NULL);
econtext = mtstate->ps.ps_ExprContext;
leaf_part_rri->ri_projectReturning =
ExecBuildProjectionInfo(returningList, econtext, slot,
&mtstate->ps, RelationGetDescr(partrel));
}
/* Set up information needed for routing tuples to the partition. */
ExecInitRoutingInfo(mtstate, estate, proute, dispatch,
leaf_part_rri, partidx);
/*
* If there is an ON CONFLICT clause, initialize state for it.
*/
if (node && node->onConflictAction != ONCONFLICT_NONE)
{
int firstVarno = mtstate->resultRelInfo[0].ri_RangeTableIndex;
TupleDesc partrelDesc = RelationGetDescr(partrel);
ExprContext *econtext = mtstate->ps.ps_ExprContext;
ListCell *lc;
List *arbiterIndexes = NIL;
/*
* If there is a list of arbiter indexes, map it to a list of indexes
* in the partition. We do that by scanning the partition's index
* list and searching for ancestry relationships to each index in the
* ancestor table.
*/
if (list_length(rootResultRelInfo->ri_onConflictArbiterIndexes) > 0)
{
List *childIdxs;
childIdxs = RelationGetIndexList(leaf_part_rri->ri_RelationDesc);
foreach(lc, childIdxs)
{
Oid childIdx = lfirst_oid(lc);
List *ancestors;
ListCell *lc2;
ancestors = get_partition_ancestors(childIdx);
foreach(lc2, rootResultRelInfo->ri_onConflictArbiterIndexes)
{
if (list_member_oid(ancestors, lfirst_oid(lc2)))
arbiterIndexes = lappend_oid(arbiterIndexes, childIdx);
}
list_free(ancestors);
}
}
/*
* If the resulting lists are of inequal length, something is wrong.
* (This shouldn't happen, since arbiter index selection should not
* pick up an invalid index.)
*/
if (list_length(rootResultRelInfo->ri_onConflictArbiterIndexes) !=
list_length(arbiterIndexes))
elog(ERROR, "invalid arbiter index list");
leaf_part_rri->ri_onConflictArbiterIndexes = arbiterIndexes;
/*
* In the DO UPDATE case, we have some more state to initialize.
*/
if (node->onConflictAction == ONCONFLICT_UPDATE)
{
TupleConversionMap *map;
map = leaf_part_rri->ri_PartitionInfo->pi_RootToPartitionMap;
Assert(node->onConflictSet != NIL);
Assert(rootResultRelInfo->ri_onConflict != NULL);
leaf_part_rri->ri_onConflict = makeNode(OnConflictSetState);
/*
* Need a separate existing slot for each partition, as the
* partition could be of a different AM, even if the tuple
* descriptors match.
*/
leaf_part_rri->ri_onConflict->oc_Existing =
table_slot_create(leaf_part_rri->ri_RelationDesc,
&mtstate->ps.state->es_tupleTable);
/*
* If the partition's tuple descriptor matches exactly the root
* parent (the common case), we can re-use most of the parent's ON
* CONFLICT SET state, skipping a bunch of work. Otherwise, we
* need to create state specific to this partition.
*/
if (map == NULL)
{
/*
* It's safe to reuse these from the partition root, as we
* only process one tuple at a time (therefore we won't
* overwrite needed data in slots), and the results of
* projections are independent of the underlying storage.
* Projections and where clauses themselves don't store state
* / are independent of the underlying storage.
*/
leaf_part_rri->ri_onConflict->oc_ProjSlot =
rootResultRelInfo->ri_onConflict->oc_ProjSlot;
leaf_part_rri->ri_onConflict->oc_ProjInfo =
rootResultRelInfo->ri_onConflict->oc_ProjInfo;
leaf_part_rri->ri_onConflict->oc_WhereClause =
rootResultRelInfo->ri_onConflict->oc_WhereClause;
}
else
{
List *onconflset;
TupleDesc tupDesc;
bool found_whole_row;
/*
* Translate expressions in onConflictSet to account for
* different attribute numbers. For that, map partition
* varattnos twice: first to catch the EXCLUDED
* pseudo-relation (INNER_VAR), and second to handle the main
* target relation (firstVarno).
*/
onconflset = (List *) copyObject((Node *) node->onConflictSet);
if (part_attmap == NULL)
part_attmap =
build_attrmap_by_name(RelationGetDescr(partrel),
RelationGetDescr(firstResultRel));
onconflset = (List *)
map_variable_attnos((Node *) onconflset,
INNER_VAR, 0,
part_attmap,
RelationGetForm(partrel)->reltype,
&found_whole_row);
/* We ignore the value of found_whole_row. */
onconflset = (List *)
map_variable_attnos((Node *) onconflset,
firstVarno, 0,
part_attmap,
RelationGetForm(partrel)->reltype,
&found_whole_row);
/* We ignore the value of found_whole_row. */
/* Finally, adjust this tlist to match the partition. */
onconflset = adjust_partition_tlist(onconflset, map);
/* create the tuple slot for the UPDATE SET projection */
tupDesc = ExecTypeFromTL(onconflset);
leaf_part_rri->ri_onConflict->oc_ProjSlot =
ExecInitExtraTupleSlot(mtstate->ps.state, tupDesc,
&TTSOpsVirtual);
/* build UPDATE SET projection state */
leaf_part_rri->ri_onConflict->oc_ProjInfo =
ExecBuildProjectionInfo(onconflset, econtext,
leaf_part_rri->ri_onConflict->oc_ProjSlot,
&mtstate->ps, partrelDesc);
/*
* If there is a WHERE clause, initialize state where it will
* be evaluated, mapping the attribute numbers appropriately.
* As with onConflictSet, we need to map partition varattnos
* to the partition's tupdesc.
*/
if (node->onConflictWhere)
{
List *clause;
clause = copyObject((List *) node->onConflictWhere);
clause = (List *)
map_variable_attnos((Node *) clause,
INNER_VAR, 0,
part_attmap,
RelationGetForm(partrel)->reltype,
&found_whole_row);
/* We ignore the value of found_whole_row. */
clause = (List *)
map_variable_attnos((Node *) clause,
firstVarno, 0,
part_attmap,
RelationGetForm(partrel)->reltype,
&found_whole_row);
/* We ignore the value of found_whole_row. */
leaf_part_rri->ri_onConflict->oc_WhereClause =
ExecInitQual((List *) clause, &mtstate->ps);
}
}
}
}
/*
* Since we've just initialized this ResultRelInfo, it's not in any list
* attached to the estate as yet. Add it, so that it can be found later.
*
* Note that the entries in this list appear in no predetermined order,
* because partition result rels are initialized as and when they're
* needed.
*/
MemoryContextSwitchTo(estate->es_query_cxt);
estate->es_tuple_routing_result_relations =
lappend(estate->es_tuple_routing_result_relations,
leaf_part_rri);
MemoryContextSwitchTo(oldcxt);
return leaf_part_rri;
}
/*
* ExecInitRoutingInfo
* Set up information needed for translating tuples between root
* partitioned table format and partition format, and keep track of it
* in PartitionTupleRouting.
*/
static void
ExecInitRoutingInfo(ModifyTableState *mtstate,
EState *estate,
PartitionTupleRouting *proute,
PartitionDispatch dispatch,
ResultRelInfo *partRelInfo,
int partidx)
{
MemoryContext oldcxt;
PartitionRoutingInfo *partrouteinfo;
int rri_index;
oldcxt = MemoryContextSwitchTo(proute->memcxt);
partrouteinfo = palloc(sizeof(PartitionRoutingInfo));
/*
* Set up a tuple conversion map to convert a tuple routed to the
* partition from the parent's type to the partition's.
*/
partrouteinfo->pi_RootToPartitionMap =
convert_tuples_by_name(RelationGetDescr(partRelInfo->ri_PartitionRoot),
RelationGetDescr(partRelInfo->ri_RelationDesc));
/*
* If a partition has a different rowtype than the root parent, initialize
* a slot dedicated to storing this partition's tuples. The slot is used
* for various operations that are applied to tuples after routing, such
* as checking constraints.
*/
if (partrouteinfo->pi_RootToPartitionMap != NULL)
{
Relation partrel = partRelInfo->ri_RelationDesc;
/*
* Initialize the slot itself setting its descriptor to this
* partition's TupleDesc; TupleDesc reference will be released at the
* end of the command.
*/
partrouteinfo->pi_PartitionTupleSlot =
table_slot_create(partrel, &estate->es_tupleTable);
}
else
partrouteinfo->pi_PartitionTupleSlot = NULL;
/*
* Also, if transition capture is required, store a map to convert tuples
* from partition's rowtype to the root partition table's.
*/
if (mtstate &&
(mtstate->mt_transition_capture || mtstate->mt_oc_transition_capture))
{
partrouteinfo->pi_PartitionToRootMap =
convert_tuples_by_name(RelationGetDescr(partRelInfo->ri_RelationDesc),
RelationGetDescr(partRelInfo->ri_PartitionRoot));
}
else
partrouteinfo->pi_PartitionToRootMap = NULL;
/*
* If the partition is a foreign table, let the FDW init itself for
* routing tuples to the partition.
*/
if (partRelInfo->ri_FdwRoutine != NULL &&
partRelInfo->ri_FdwRoutine->BeginForeignInsert != NULL)
partRelInfo->ri_FdwRoutine->BeginForeignInsert(mtstate, partRelInfo);
partRelInfo->ri_PartitionInfo = partrouteinfo;
partRelInfo->ri_CopyMultiInsertBuffer = NULL;
/*
* Keep track of it in the PartitionTupleRouting->partitions array.
*/
Assert(dispatch->indexes[partidx] == -1);
rri_index = proute->num_partitions++;
/* Allocate or enlarge the array, as needed */
if (proute->num_partitions >= proute->max_partitions)
{
if (proute->max_partitions == 0)
{
proute->max_partitions = 8;
proute->partitions = (ResultRelInfo **)
palloc(sizeof(ResultRelInfo *) * proute->max_partitions);
}
else
{
proute->max_partitions *= 2;
proute->partitions = (ResultRelInfo **)
repalloc(proute->partitions, sizeof(ResultRelInfo *) *
proute->max_partitions);
}
}
proute->partitions[rri_index] = partRelInfo;
dispatch->indexes[partidx] = rri_index;
MemoryContextSwitchTo(oldcxt);
}
/*
* ExecInitPartitionDispatchInfo
* Lock the partitioned table (if not locked already) and initialize
* PartitionDispatch for a partitioned table and store it in the next
* available slot in the proute->partition_dispatch_info array. Also,
* record the index into this array in the parent_pd->indexes[] array in
* the partidx element so that we can properly retrieve the newly created
* PartitionDispatch later.
*/
static PartitionDispatch
ExecInitPartitionDispatchInfo(EState *estate,
PartitionTupleRouting *proute, Oid partoid,
PartitionDispatch parent_pd, int partidx)
{
Relation rel;
PartitionDesc partdesc;
PartitionDispatch pd;
int dispatchidx;
MemoryContext oldcxt;
if (estate->es_partition_directory == NULL)
estate->es_partition_directory =
CreatePartitionDirectory(estate->es_query_cxt);
oldcxt = MemoryContextSwitchTo(proute->memcxt);
/*
* Only sub-partitioned tables need to be locked here. The root
* partitioned table will already have been locked as it's referenced in
* the query's rtable.
*/
if (partoid != RelationGetRelid(proute->partition_root))
rel = table_open(partoid, RowExclusiveLock);
else
rel = proute->partition_root;
partdesc = PartitionDirectoryLookup(estate->es_partition_directory, rel);
pd = (PartitionDispatch) palloc(offsetof(PartitionDispatchData, indexes) +
partdesc->nparts * sizeof(int));
pd->reldesc = rel;
pd->key = RelationGetPartitionKey(rel);
pd->keystate = NIL;
pd->partdesc = partdesc;
if (parent_pd != NULL)
{
TupleDesc tupdesc = RelationGetDescr(rel);
/*
* For sub-partitioned tables where the column order differs from its
* direct parent partitioned table, we must store a tuple table slot
* initialized with its tuple descriptor and a tuple conversion map to
* convert a tuple from its parent's rowtype to its own. This is to
* make sure that we are looking at the correct row using the correct
* tuple descriptor when computing its partition key for tuple
* routing.
*/
pd->tupmap = build_attrmap_by_name_if_req(RelationGetDescr(parent_pd->reldesc),
tupdesc);
pd->tupslot = pd->tupmap ?
MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual) : NULL;
}
else
{
/* Not required for the root partitioned table */
pd->tupmap = NULL;
pd->tupslot = NULL;
}
/*
* Initialize with -1 to signify that the corresponding partition's
* ResultRelInfo or PartitionDispatch has not been created yet.
*/
memset(pd->indexes, -1, sizeof(int) * partdesc->nparts);
/* Track in PartitionTupleRouting for later use */
dispatchidx = proute->num_dispatch++;
/* Allocate or enlarge the array, as needed */
if (proute->num_dispatch >= proute->max_dispatch)
{
if (proute->max_dispatch == 0)
{
proute->max_dispatch = 4;
proute->partition_dispatch_info = (PartitionDispatch *)
palloc(sizeof(PartitionDispatch) * proute->max_dispatch);
proute->nonleaf_partitions = (ResultRelInfo **)
palloc(sizeof(ResultRelInfo *) * proute->max_dispatch);
}
else
{
proute->max_dispatch *= 2;
proute->partition_dispatch_info = (PartitionDispatch *)
repalloc(proute->partition_dispatch_info,
sizeof(PartitionDispatch) * proute->max_dispatch);
proute->nonleaf_partitions = (ResultRelInfo **)
repalloc(proute->nonleaf_partitions,
sizeof(ResultRelInfo *) * proute->max_dispatch);
}
}
proute->partition_dispatch_info[dispatchidx] = pd;
/*
* If setting up a PartitionDispatch for a sub-partitioned table, we may
* also need a minimally valid ResultRelInfo for checking the partition
* constraint later; set that up now.
*/
if (parent_pd)
{
ResultRelInfo *rri = makeNode(ResultRelInfo);
InitResultRelInfo(rri, rel, 1, proute->partition_root, 0);
proute->nonleaf_partitions[dispatchidx] = rri;
}
else
proute->nonleaf_partitions[dispatchidx] = NULL;
/*
* Finally, if setting up a PartitionDispatch for a sub-partitioned table,
* install a downlink in the parent to allow quick descent.
*/
if (parent_pd)
{
Assert(parent_pd->indexes[partidx] == -1);
parent_pd->indexes[partidx] = dispatchidx;
}
MemoryContextSwitchTo(oldcxt);
return pd;
}
/*
* ExecCleanupTupleRouting -- Clean up objects allocated for partition tuple
* routing.
*
* Close all the partitioned tables, leaf partitions, and their indices.
*/
void
ExecCleanupTupleRouting(ModifyTableState *mtstate,
PartitionTupleRouting *proute)
{
HTAB *htab = proute->subplan_resultrel_htab;
int i;
/*
* Remember, proute->partition_dispatch_info[0] corresponds to the root
* partitioned table, which we must not try to close, because it is the
* main target table of the query that will be closed by callers such as
* ExecEndPlan() or DoCopy(). Also, tupslot is NULL for the root
* partitioned table.
*/
for (i = 1; i < proute->num_dispatch; i++)
{
PartitionDispatch pd = proute->partition_dispatch_info[i];
table_close(pd->reldesc, NoLock);
if (pd->tupslot)
ExecDropSingleTupleTableSlot(pd->tupslot);
}
for (i = 0; i < proute->num_partitions; i++)
{
ResultRelInfo *resultRelInfo = proute->partitions[i];
/* Allow any FDWs to shut down */
if (resultRelInfo->ri_FdwRoutine != NULL &&
resultRelInfo->ri_FdwRoutine->EndForeignInsert != NULL)
resultRelInfo->ri_FdwRoutine->EndForeignInsert(mtstate->ps.state,
resultRelInfo);
/*
* Check if this result rel is one belonging to the node's subplans,
* if so, let ExecEndPlan() clean it up.
*/
if (htab)
{
Oid partoid;
bool found;
partoid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
(void) hash_search(htab, &partoid, HASH_FIND, &found);
if (found)
continue;
}
ExecCloseIndices(resultRelInfo);
table_close(resultRelInfo->ri_RelationDesc, NoLock);
}
}
/* ----------------
* FormPartitionKeyDatum
* Construct values[] and isnull[] arrays for the partition key
* of a tuple.
*
* pd Partition dispatch object of the partitioned table
* slot Heap tuple from which to extract partition key
* estate executor state for evaluating any partition key
* expressions (must be non-NULL)
* values Array of partition key Datums (output area)
* isnull Array of is-null indicators (output area)
*
* the ecxt_scantuple slot of estate's per-tuple expr context must point to
* the heap tuple passed in.
* ----------------
*/
static void
FormPartitionKeyDatum(PartitionDispatch pd,
TupleTableSlot *slot,
EState *estate,
Datum *values,
bool *isnull)
{
ListCell *partexpr_item;
int i;
if (pd->key->partexprs != NIL && pd->keystate == NIL)
{
/* Check caller has set up context correctly */
Assert(estate != NULL &&
GetPerTupleExprContext(estate)->ecxt_scantuple == slot);
/* First time through, set up expression evaluation state */
pd->keystate = ExecPrepareExprList(pd->key->partexprs, estate);
}
partexpr_item = list_head(pd->keystate);
for (i = 0; i < pd->key->partnatts; i++)
{
AttrNumber keycol = pd->key->partattrs[i];
Datum datum;
bool isNull;
if (keycol != 0)
{
/* Plain column; get the value directly from the heap tuple */
datum = slot_getattr(slot, keycol, &isNull);
}
else
{
/* Expression; need to evaluate it */
if (partexpr_item == NULL)
elog(ERROR, "wrong number of partition key expressions");
datum = ExecEvalExprSwitchContext((ExprState *) lfirst(partexpr_item),
GetPerTupleExprContext(estate),
&isNull);
partexpr_item = lnext(pd->keystate, partexpr_item);
}
values[i] = datum;
isnull[i] = isNull;
}
if (partexpr_item != NULL)
elog(ERROR, "wrong number of partition key expressions");
}
/*
* get_partition_for_tuple
* Finds partition of relation which accepts the partition key specified
* in values and isnull
*
* Return value is index of the partition (>= 0 and < partdesc->nparts) if one
* found or -1 if none found.
*/
static int
get_partition_for_tuple(PartitionDispatch pd, Datum *values, bool *isnull)
{
int bound_offset;
int part_index = -1;
PartitionKey key = pd->key;
PartitionDesc partdesc = pd->partdesc;
PartitionBoundInfo boundinfo = partdesc->boundinfo;
/* Route as appropriate based on partitioning strategy. */
switch (key->strategy)
{
case PARTITION_STRATEGY_HASH:
{
int greatest_modulus;
uint64 rowHash;
greatest_modulus = get_hash_partition_greatest_modulus(boundinfo);
rowHash = compute_partition_hash_value(key->partnatts,
key->partsupfunc,
key->partcollation,
values, isnull);
part_index = boundinfo->indexes[rowHash % greatest_modulus];
}
break;
case PARTITION_STRATEGY_LIST:
if (isnull[0])
{
if (partition_bound_accepts_nulls(boundinfo))
part_index = boundinfo->null_index;
}
else
{
bool equal = false;
bound_offset = partition_list_bsearch(key->partsupfunc,
key->partcollation,
boundinfo,
values[0], &equal);
if (bound_offset >= 0 && equal)
part_index = boundinfo->indexes[bound_offset];
}
break;
case PARTITION_STRATEGY_RANGE:
{
bool equal = false,
range_partkey_has_null = false;
int i;
/*
* No range includes NULL, so this will be accepted by the
* default partition if there is one, and otherwise rejected.
*/
for (i = 0; i < key->partnatts; i++)
{
if (isnull[i])
{
range_partkey_has_null = true;
break;
}
}
if (!range_partkey_has_null)
{
bound_offset = partition_range_datum_bsearch(key->partsupfunc,
key->partcollation,
boundinfo,
key->partnatts,
values,
&equal);
/*
* The bound at bound_offset is less than or equal to the
* tuple value, so the bound at offset+1 is the upper
* bound of the partition we're looking for, if there
* actually exists one.
*/
part_index = boundinfo->indexes[bound_offset + 1];
}
}
break;
default:
elog(ERROR, "unexpected partition strategy: %d",
(int) key->strategy);
}
/*
* part_index < 0 means we failed to find a partition of this parent. Use
* the default partition, if there is one.
*/
if (part_index < 0)
part_index = boundinfo->default_index;
return part_index;
}
/*
* ExecBuildSlotPartitionKeyDescription
*
* This works very much like BuildIndexValueDescription() and is currently
* used for building error messages when ExecFindPartition() fails to find
* partition for a row.
*/
static char *
ExecBuildSlotPartitionKeyDescription(Relation rel,
Datum *values,
bool *isnull,
int maxfieldlen)
{
StringInfoData buf;
PartitionKey key = RelationGetPartitionKey(rel);
int partnatts = get_partition_natts(key);
int i;
Oid relid = RelationGetRelid(rel);
AclResult aclresult;
if (check_enable_rls(relid, InvalidOid, true) == RLS_ENABLED)
return NULL;
/* If the user has table-level access, just go build the description. */
aclresult = pg_class_aclcheck(relid, GetUserId(), ACL_SELECT);
if (aclresult != ACLCHECK_OK)
{
/*
* Step through the columns of the partition key and make sure the
* user has SELECT rights on all of them.
*/
for (i = 0; i < partnatts; i++)
{
AttrNumber attnum = get_partition_col_attnum(key, i);
/*
* If this partition key column is an expression, we return no
* detail rather than try to figure out what column(s) the
* expression includes and if the user has SELECT rights on them.
*/
if (attnum == InvalidAttrNumber ||
pg_attribute_aclcheck(relid, attnum, GetUserId(),
ACL_SELECT) != ACLCHECK_OK)
return NULL;
}
}
initStringInfo(&buf);
appendStringInfo(&buf, "(%s) = (",
pg_get_partkeydef_columns(relid, true));
for (i = 0; i < partnatts; i++)
{
char *val;
int vallen;
if (isnull[i])
val = "null";
else
{
Oid foutoid;
bool typisvarlena;
getTypeOutputInfo(get_partition_col_typid(key, i),
&foutoid, &typisvarlena);
val = OidOutputFunctionCall(foutoid, values[i]);
}
if (i > 0)
appendStringInfoString(&buf, ", ");
/* truncate if needed */
vallen = strlen(val);
if (vallen <= maxfieldlen)
appendBinaryStringInfo(&buf, val, vallen);
else
{
vallen = pg_mbcliplen(val, vallen, maxfieldlen);
appendBinaryStringInfo(&buf, val, vallen);
appendStringInfoString(&buf, "...");
}
}
appendStringInfoChar(&buf, ')');
return buf.data;
}
/*
* adjust_partition_tlist
* Adjust the targetlist entries for a given partition to account for
* attribute differences between parent and the partition
*
* The expressions have already been fixed, but here we fix the list to make
* target resnos match the partition's attribute numbers. This results in a
* copy of the original target list in which the entries appear in resno
* order, including both the existing entries (that may have their resno
* changed in-place) and the newly added entries for columns that don't exist
* in the parent.
*
* Scribbles on the input tlist, so callers must make sure to make a copy
* before passing it to us.
*/
static List *
adjust_partition_tlist(List *tlist, TupleConversionMap *map)
{
List *new_tlist = NIL;
TupleDesc tupdesc = map->outdesc;
AttrMap *attrMap = map->attrMap;
AttrNumber attrno;
Assert(tupdesc->natts == attrMap->maplen);
for (attrno = 1; attrno <= tupdesc->natts; attrno++)
{
Form_pg_attribute att_tup = TupleDescAttr(tupdesc, attrno - 1);
TargetEntry *tle;
if (attrMap->attnums[attrno - 1] != InvalidAttrNumber)
{
Assert(!att_tup->attisdropped);
/*
* Use the corresponding entry from the parent's tlist, adjusting
* the resno the match the partition's attno.
*/
tle = (TargetEntry *) list_nth(tlist, attrMap->attnums[attrno - 1] - 1);
tle->resno = attrno;
}
else
{
Const *expr;
/*
* For a dropped attribute in the partition, generate a dummy
* entry with resno matching the partition's attno.
*/
Assert(att_tup->attisdropped);
expr = makeConst(INT4OID,
-1,
InvalidOid,
sizeof(int32),
(Datum) 0,
true, /* isnull */
true /* byval */ );
tle = makeTargetEntry((Expr *) expr,
attrno,
pstrdup(NameStr(att_tup->attname)),
false);
}
new_tlist = lappend(new_tlist, tle);
}
return new_tlist;
}
/*-------------------------------------------------------------------------
* Run-Time Partition Pruning Support.
*
* The following series of functions exist to support the removal of unneeded
* subplans for queries against partitioned tables. The supporting functions
* here are designed to work with any plan type which supports an arbitrary
* number of subplans, e.g. Append, MergeAppend.
*
* When pruning involves comparison of a partition key to a constant, it's
* done by the planner. However, if we have a comparison to a non-constant
* but not volatile expression, that presents an opportunity for run-time
* pruning by the executor, allowing irrelevant partitions to be skipped
* dynamically.
*
* We must distinguish expressions containing PARAM_EXEC Params from
* expressions that don't contain those. Even though a PARAM_EXEC Param is
* considered to be a stable expression, it can change value from one plan
* node scan to the next during query execution. Stable comparison
* expressions that don't involve such Params allow partition pruning to be
* done once during executor startup. Expressions that do involve such Params
* require us to prune separately for each scan of the parent plan node.
*
* Note that pruning away unneeded subplans during executor startup has the
* added benefit of not having to initialize the unneeded subplans at all.
*
*
* Functions:
*
* ExecCreatePartitionPruneState:
* Creates the PartitionPruneState required by each of the two pruning
* functions. Details stored include how to map the partition index
* returned by the partition pruning code into subplan indexes.
*
* ExecFindInitialMatchingSubPlans:
* Returns indexes of matching subplans. Partition pruning is attempted
* without any evaluation of expressions containing PARAM_EXEC Params.
* This function must be called during executor startup for the parent
* plan before the subplans themselves are initialized. Subplans which
* are found not to match by this function must be removed from the
* plan's list of subplans during execution, as this function performs a
* remap of the partition index to subplan index map and the newly
* created map provides indexes only for subplans which remain after
* calling this function.
*
* ExecFindMatchingSubPlans:
* Returns indexes of matching subplans after evaluating all available
* expressions. This function can only be called during execution and
* must be called again each time the value of a Param listed in
* PartitionPruneState's 'execparamids' changes.
*-------------------------------------------------------------------------
*/
/*
* ExecCreatePartitionPruneState
* Build the data structure required for calling
* ExecFindInitialMatchingSubPlans and ExecFindMatchingSubPlans.
*
* 'planstate' is the parent plan node's execution state.
*
* 'partitionpruneinfo' is a PartitionPruneInfo as generated by
* make_partition_pruneinfo. Here we build a PartitionPruneState containing a
* PartitionPruningData for each partitioning hierarchy (i.e., each sublist of
* partitionpruneinfo->prune_infos), each of which contains a
* PartitionedRelPruningData for each PartitionedRelPruneInfo appearing in
* that sublist. This two-level system is needed to keep from confusing the
* different hierarchies when a UNION ALL contains multiple partitioned tables
* as children. The data stored in each PartitionedRelPruningData can be
* re-used each time we re-evaluate which partitions match the pruning steps
* provided in each PartitionedRelPruneInfo.
*/
PartitionPruneState *
ExecCreatePartitionPruneState(PlanState *planstate,
PartitionPruneInfo *partitionpruneinfo)
{
EState *estate = planstate->state;
PartitionPruneState *prunestate;
int n_part_hierarchies;
ListCell *lc;
int i;
if (estate->es_partition_directory == NULL)
estate->es_partition_directory =
CreatePartitionDirectory(estate->es_query_cxt);
n_part_hierarchies = list_length(partitionpruneinfo->prune_infos);
Assert(n_part_hierarchies > 0);
/*
* Allocate the data structure
*/
prunestate = (PartitionPruneState *)
palloc(offsetof(PartitionPruneState, partprunedata) +
sizeof(PartitionPruningData *) * n_part_hierarchies);
prunestate->execparamids = NULL;
/* other_subplans can change at runtime, so we need our own copy */
prunestate->other_subplans = bms_copy(partitionpruneinfo->other_subplans);
prunestate->do_initial_prune = false; /* may be set below */
prunestate->do_exec_prune = false; /* may be set below */
prunestate->num_partprunedata = n_part_hierarchies;
/*
* Create a short-term memory context which we'll use when making calls to
* the partition pruning functions. This avoids possible memory leaks,
* since the pruning functions call comparison functions that aren't under
* our control.
*/
prunestate->prune_context =
AllocSetContextCreate(CurrentMemoryContext,
"Partition Prune",
ALLOCSET_DEFAULT_SIZES);
i = 0;
foreach(lc, partitionpruneinfo->prune_infos)
{
List *partrelpruneinfos = lfirst_node(List, lc);
int npartrelpruneinfos = list_length(partrelpruneinfos);
PartitionPruningData *prunedata;
ListCell *lc2;
int j;
prunedata = (PartitionPruningData *)
palloc(offsetof(PartitionPruningData, partrelprunedata) +
npartrelpruneinfos * sizeof(PartitionedRelPruningData));
prunestate->partprunedata[i] = prunedata;
prunedata->num_partrelprunedata = npartrelpruneinfos;
j = 0;
foreach(lc2, partrelpruneinfos)
{
PartitionedRelPruneInfo *pinfo = lfirst_node(PartitionedRelPruneInfo, lc2);
PartitionedRelPruningData *pprune = &prunedata->partrelprunedata[j];
Relation partrel;
PartitionDesc partdesc;
PartitionKey partkey;
/*
* We can rely on the copies of the partitioned table's partition
* key and partition descriptor appearing in its relcache entry,
* because that entry will be held open and locked for the
* duration of this executor run.
*/
partrel = ExecGetRangeTableRelation(estate, pinfo->rtindex);
partkey = RelationGetPartitionKey(partrel);
partdesc = PartitionDirectoryLookup(estate->es_partition_directory,
partrel);
/*
* Initialize the subplan_map and subpart_map. Since detaching a
* partition requires AccessExclusiveLock, no partitions can have
* disappeared, nor can the bounds for any partition have changed.
* However, new partitions may have been added.
*/
Assert(partdesc->nparts >= pinfo->nparts);
pprune->nparts = partdesc->nparts;
pprune->subplan_map = palloc(sizeof(int) * partdesc->nparts);
if (partdesc->nparts == pinfo->nparts)
{
/*
* There are no new partitions, so this is simple. We can
* simply point to the subpart_map from the plan, but we must
* copy the subplan_map since we may change it later.
*/
pprune->subpart_map = pinfo->subpart_map;
memcpy(pprune->subplan_map, pinfo->subplan_map,
sizeof(int) * pinfo->nparts);
/*
* Double-check that the list of unpruned relations has not
* changed. (Pruned partitions are not in relid_map[].)
*/
#ifdef USE_ASSERT_CHECKING
for (int k = 0; k < pinfo->nparts; k++)
{
Assert(partdesc->oids[k] == pinfo->relid_map[k] ||
pinfo->subplan_map[k] == -1);
}
#endif
}
else
{
int pd_idx = 0;
int pp_idx;
/*
* Some new partitions have appeared since plan time, and
* those are reflected in our PartitionDesc but were not
* present in the one used to construct subplan_map and
* subpart_map. So we must construct new and longer arrays
* where the partitions that were originally present map to
* the same sub-structures, and any added partitions map to
* -1, as if the new partitions had been pruned.
*
* Note: pinfo->relid_map[] may contain InvalidOid entries for
* partitions pruned by the planner. We cannot tell exactly
* which of the partdesc entries these correspond to, but we
* don't have to; just skip over them. The non-pruned
* relid_map entries, however, had better be a subset of the
* partdesc entries and in the same order.
*/
pprune->subpart_map = palloc(sizeof(int) * partdesc->nparts);
for (pp_idx = 0; pp_idx < partdesc->nparts; pp_idx++)
{
/* Skip any InvalidOid relid_map entries */
while (pd_idx < pinfo->nparts &&
!OidIsValid(pinfo->relid_map[pd_idx]))
pd_idx++;
if (pd_idx < pinfo->nparts &&
pinfo->relid_map[pd_idx] == partdesc->oids[pp_idx])
{
/* match... */
pprune->subplan_map[pp_idx] =
pinfo->subplan_map[pd_idx];
pprune->subpart_map[pp_idx] =
pinfo->subpart_map[pd_idx];
pd_idx++;
}
else
{
/* this partdesc entry is not in the plan */
pprune->subplan_map[pp_idx] = -1;
pprune->subpart_map[pp_idx] = -1;
}
}
/*
* It might seem that we need to skip any trailing InvalidOid
* entries in pinfo->relid_map before checking that we scanned
* all of the relid_map. But we will have skipped them above,
* because they must correspond to some partdesc->oids
* entries; we just couldn't tell which.
*/
if (pd_idx != pinfo->nparts)
elog(ERROR, "could not match partition child tables to plan elements");
}
/* present_parts is also subject to later modification */
pprune->present_parts = bms_copy(pinfo->present_parts);
/*
* Initialize pruning contexts as needed.
*/
pprune->initial_pruning_steps = pinfo->initial_pruning_steps;
if (pinfo->initial_pruning_steps)
{
ExecInitPruningContext(&pprune->initial_context,
pinfo->initial_pruning_steps,
partdesc, partkey, planstate);
/* Record whether initial pruning is needed at any level */
prunestate->do_initial_prune = true;
}
pprune->exec_pruning_steps = pinfo->exec_pruning_steps;
if (pinfo->exec_pruning_steps)
{
ExecInitPruningContext(&pprune->exec_context,
pinfo->exec_pruning_steps,
partdesc, partkey, planstate);
/* Record whether exec pruning is needed at any level */
prunestate->do_exec_prune = true;
}
/*
* Accumulate the IDs of all PARAM_EXEC Params affecting the
* partitioning decisions at this plan node.
*/
prunestate->execparamids = bms_add_members(prunestate->execparamids,
pinfo->execparamids);
j++;
}
i++;
}
return prunestate;
}
/*
* Initialize a PartitionPruneContext for the given list of pruning steps.
*/
static void
ExecInitPruningContext(PartitionPruneContext *context,
List *pruning_steps,
PartitionDesc partdesc,
PartitionKey partkey,
PlanState *planstate)
{
int n_steps;
int partnatts;
ListCell *lc;
n_steps = list_length(pruning_steps);
context->strategy = partkey->strategy;
context->partnatts = partnatts = partkey->partnatts;
context->nparts = partdesc->nparts;
context->boundinfo = partdesc->boundinfo;
context->partcollation = partkey->partcollation;
context->partsupfunc = partkey->partsupfunc;
/* We'll look up type-specific support functions as needed */
context->stepcmpfuncs = (FmgrInfo *)
palloc0(sizeof(FmgrInfo) * n_steps * partnatts);
context->ppccontext = CurrentMemoryContext;
context->planstate = planstate;
/* Initialize expression state for each expression we need */
context->exprstates = (ExprState **)
palloc0(sizeof(ExprState *) * n_steps * partnatts);
foreach(lc, pruning_steps)
{
PartitionPruneStepOp *step = (PartitionPruneStepOp *) lfirst(lc);
ListCell *lc2;
int keyno;
/* not needed for other step kinds */
if (!IsA(step, PartitionPruneStepOp))
continue;
Assert(list_length(step->exprs) <= partnatts);
keyno = 0;
foreach(lc2, step->exprs)
{
Expr *expr = (Expr *) lfirst(lc2);
/* not needed for Consts */
if (!IsA(expr, Const))
{
int stateidx = PruneCxtStateIdx(partnatts,
step->step.step_id,
keyno);
context->exprstates[stateidx] =
ExecInitExpr(expr, context->planstate);
}
keyno++;
}
}
}
/*
* ExecFindInitialMatchingSubPlans
* Identify the set of subplans that cannot be eliminated by initial
* pruning, disregarding any pruning constraints involving PARAM_EXEC
* Params.
*
* If additional pruning passes will be required (because of PARAM_EXEC
* Params), we must also update the translation data that allows conversion
* of partition indexes into subplan indexes to account for the unneeded
* subplans having been removed.
*
* Must only be called once per 'prunestate', and only if initial pruning
* is required.
*
* 'nsubplans' must be passed as the total number of unpruned subplans.
*/
Bitmapset *
ExecFindInitialMatchingSubPlans(PartitionPruneState *prunestate, int nsubplans)
{
Bitmapset *result = NULL;
MemoryContext oldcontext;
int i;
/* Caller error if we get here without do_initial_prune */
Assert(prunestate->do_initial_prune);
/*
* Switch to a temp context to avoid leaking memory in the executor's
* query-lifespan memory context.
*/
oldcontext = MemoryContextSwitchTo(prunestate->prune_context);
/*
* For each hierarchy, do the pruning tests, and add nondeletable
* subplans' indexes to "result".
*/
for (i = 0; i < prunestate->num_partprunedata; i++)
{
PartitionPruningData *prunedata;
PartitionedRelPruningData *pprune;
prunedata = prunestate->partprunedata[i];
pprune = &prunedata->partrelprunedata[0];
/* Perform pruning without using PARAM_EXEC Params */
find_matching_subplans_recurse(prunedata, pprune, true, &result);
/* Expression eval may have used space in node's ps_ExprContext too */
if (pprune->initial_pruning_steps)
ResetExprContext(pprune->initial_context.planstate->ps_ExprContext);
}
/* Add in any subplans that partition pruning didn't account for */
result = bms_add_members(result, prunestate->other_subplans);
MemoryContextSwitchTo(oldcontext);
/* Copy result out of the temp context before we reset it */
result = bms_copy(result);
MemoryContextReset(prunestate->prune_context);
/*
* If exec-time pruning is required and we pruned subplans above, then we
* must re-sequence the subplan indexes so that ExecFindMatchingSubPlans
* properly returns the indexes from the subplans which will remain after
* execution of this function.
*
* We can safely skip this when !do_exec_prune, even though that leaves
* invalid data in prunestate, because that data won't be consulted again
* (cf initial Assert in ExecFindMatchingSubPlans).
*/
if (prunestate->do_exec_prune && bms_num_members(result) < nsubplans)
{
int *new_subplan_indexes;
Bitmapset *new_other_subplans;
int i;
int newidx;
/*
* First we must build a temporary array which maps old subplan
* indexes to new ones. For convenience of initialization, we use
* 1-based indexes in this array and leave pruned items as 0.
*/
new_subplan_indexes = (int *) palloc0(sizeof(int) * nsubplans);
newidx = 1;
i = -1;
while ((i = bms_next_member(result, i)) >= 0)
{
Assert(i < nsubplans);
new_subplan_indexes[i] = newidx++;
}
/*
* Now we can update each PartitionedRelPruneInfo's subplan_map with
* new subplan indexes. We must also recompute its present_parts
* bitmap.
*/
for (i = 0; i < prunestate->num_partprunedata; i++)
{
PartitionPruningData *prunedata = prunestate->partprunedata[i];
int j;
/*
* Within each hierarchy, we perform this loop in back-to-front
* order so that we determine present_parts for the lowest-level
* partitioned tables first. This way we can tell whether a
* sub-partitioned table's partitions were entirely pruned so we
* can exclude it from the current level's present_parts.
*/
for (j = prunedata->num_partrelprunedata - 1; j >= 0; j--)
{
PartitionedRelPruningData *pprune = &prunedata->partrelprunedata[j];
int nparts = pprune->nparts;
int k;
/* We just rebuild present_parts from scratch */
bms_free(pprune->present_parts);
pprune->present_parts = NULL;
for (k = 0; k < nparts; k++)
{
int oldidx = pprune->subplan_map[k];
int subidx;
/*
* If this partition existed as a subplan then change the
* old subplan index to the new subplan index. The new
* index may become -1 if the partition was pruned above,
* or it may just come earlier in the subplan list due to
* some subplans being removed earlier in the list. If
* it's a subpartition, add it to present_parts unless
* it's entirely pruned.
*/
if (oldidx >= 0)
{
Assert(oldidx < nsubplans);
pprune->subplan_map[k] = new_subplan_indexes[oldidx] - 1;
if (new_subplan_indexes[oldidx] > 0)
pprune->present_parts =
bms_add_member(pprune->present_parts, k);
}
else if ((subidx = pprune->subpart_map[k]) >= 0)
{
PartitionedRelPruningData *subprune;
subprune = &prunedata->partrelprunedata[subidx];
if (!bms_is_empty(subprune->present_parts))
pprune->present_parts =
bms_add_member(pprune->present_parts, k);
}
}
}
}
/*
* We must also recompute the other_subplans set, since indexes in it
* may change.
*/
new_other_subplans = NULL;
i = -1;
while ((i = bms_next_member(prunestate->other_subplans, i)) >= 0)
new_other_subplans = bms_add_member(new_other_subplans,
new_subplan_indexes[i] - 1);
bms_free(prunestate->other_subplans);
prunestate->other_subplans = new_other_subplans;
pfree(new_subplan_indexes);
}
return result;
}
/*
* ExecFindMatchingSubPlans
* Determine which subplans match the pruning steps detailed in
* 'prunestate' for the current comparison expression values.
*
* Here we assume we may evaluate PARAM_EXEC Params.
*/
Bitmapset *
ExecFindMatchingSubPlans(PartitionPruneState *prunestate)
{
Bitmapset *result = NULL;
MemoryContext oldcontext;
int i;
/*
* If !do_exec_prune, we've got problems because
* ExecFindInitialMatchingSubPlans will not have bothered to update
* prunestate for whatever pruning it did.
*/
Assert(prunestate->do_exec_prune);
/*
* Switch to a temp context to avoid leaking memory in the executor's
* query-lifespan memory context.
*/
oldcontext = MemoryContextSwitchTo(prunestate->prune_context);
/*
* For each hierarchy, do the pruning tests, and add nondeletable
* subplans' indexes to "result".
*/
for (i = 0; i < prunestate->num_partprunedata; i++)
{
PartitionPruningData *prunedata;
PartitionedRelPruningData *pprune;
prunedata = prunestate->partprunedata[i];
pprune = &prunedata->partrelprunedata[0];
find_matching_subplans_recurse(prunedata, pprune, false, &result);
/* Expression eval may have used space in node's ps_ExprContext too */
if (pprune->exec_pruning_steps)
ResetExprContext(pprune->exec_context.planstate->ps_ExprContext);
}
/* Add in any subplans that partition pruning didn't account for */
result = bms_add_members(result, prunestate->other_subplans);
MemoryContextSwitchTo(oldcontext);
/* Copy result out of the temp context before we reset it */
result = bms_copy(result);
MemoryContextReset(prunestate->prune_context);
return result;
}
/*
* find_matching_subplans_recurse
* Recursive worker function for ExecFindMatchingSubPlans and
* ExecFindInitialMatchingSubPlans
*
* Adds valid (non-prunable) subplan IDs to *validsubplans
*/
static void
find_matching_subplans_recurse(PartitionPruningData *prunedata,
PartitionedRelPruningData *pprune,
bool initial_prune,
Bitmapset **validsubplans)
{
Bitmapset *partset;
int i;
/* Guard against stack overflow due to overly deep partition hierarchy. */
check_stack_depth();
/* Only prune if pruning would be useful at this level. */
if (initial_prune && pprune->initial_pruning_steps)
{
partset = get_matching_partitions(&pprune->initial_context,
pprune->initial_pruning_steps);
}
else if (!initial_prune && pprune->exec_pruning_steps)
{
partset = get_matching_partitions(&pprune->exec_context,
pprune->exec_pruning_steps);
}
else
{
/*
* If no pruning is to be done, just include all partitions at this
* level.
*/
partset = pprune->present_parts;
}
/* Translate partset into subplan indexes */
i = -1;
while ((i = bms_next_member(partset, i)) >= 0)
{
if (pprune->subplan_map[i] >= 0)
*validsubplans = bms_add_member(*validsubplans,
pprune->subplan_map[i]);
else
{
int partidx = pprune->subpart_map[i];
if (partidx >= 0)
find_matching_subplans_recurse(prunedata,
&prunedata->partrelprunedata[partidx],
initial_prune, validsubplans);
else
{
/*
* We get here if the planner already pruned all the sub-
* partitions for this partition. Silently ignore this
* partition in this case. The end result is the same: we
* would have pruned all partitions just the same, but we
* don't have any pruning steps to execute to verify this.
*/
}
}
}
}
Reference in New Issue View Git Blame Copy Permalink