greenplumn aocsam_handler 源码
greenplumn aocsam_handler 代码
文件路径：/src/backend/access/aocs/aocsam_handler.c
/*--------------------------------------------------------------------------
*
* aocsam_handler.c
* Append only columnar access methods handler
*
* Portions Copyright (c) 2009-2010, Greenplum Inc.
* Portions Copyright (c) 2012-Present VMware, Inc. or its affiliates.
*
*
* IDENTIFICATION
* src/backend/access/aocs/aocsam_handler.c
*
*--------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/aomd.h"
#include "access/appendonlywriter.h"
#include "access/heapam.h"
#include "access/multixact.h"
#include "access/tableam.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#include "catalog/pg_am.h"
#include "catalog/pg_appendonly.h"
#include "catalog/storage.h"
#include "catalog/storage_xlog.h"
#include "cdb/cdbaocsam.h"
#include "cdb/cdbvars.h"
#include "commands/vacuum.h"
#include "executor/executor.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "pgstat.h"
#include "storage/lmgr.h"
#include "storage/procarray.h"
#include "storage/smgr.h"
#include "utils/builtins.h"
#include "utils/faultinjector.h"
#include "utils/lsyscache.h"
#include "utils/pg_rusage.h"
#define IS_BTREE(r) ((r)->rd_rel->relam == BTREE_AM_OID)
/*
* Used for bitmapHeapScan. Also look at the comment in cdbaocsam.h regarding
* AOCSScanDescIdentifier.
*
* In BitmapHeapScans, it is needed to keep track of two distict fetch
* descriptors. One for direct fetches, and another one for recheck fetches. The
* distinction allows for a different set of columns to be populated in each
* case. During initialiazation of this structure, it is required to populate
* the proj array accordingly. It is later, during the actual fetching of the
* tuple, that the corresponding fetch descriptor will be lazily initialized.
*
* Finally, in this struct, state between next_block and next_tuple calls is
* kept, in order to minimize the work that is done in the latter.
*/
typedef struct AOCSBitmapScanData
{
TableScanDescData rs_base; /* AM independent part of the descriptor */
enum AOCSScanDescIdentifier descIdentifier;
Snapshot appendOnlyMetaDataSnapshot;
enum
{
NO_RECHECK,
RECHECK
} whichDesc;
struct {
struct AOCSFetchDescData *bitmapFetch;
bool *proj;
} bitmapScanDesc[2];
int rs_cindex; /* current tuple's index tbmres->offset or -1 */
} *AOCSBitmapScan;
typedef struct AOCODMLState
{
Oid relationOid;
AOCSInsertDesc insertDesc;
AOCSDeleteDesc deleteDesc;
} AOCODMLState;
static void reset_state_cb(void *arg);
/*
* GPDB_12_MERGE_FIXME: This is a temporary state of things. A locally stored
* state is needed currently because there is no viable place to store this
* information outside of the table access method. Ideally the caller should be
* responsible for initializing a state and passing it over using the table
* access method api.
*
* Until this is in place, the local state is not to be accessed directly but
* only via the *_dml_state functions.
* It contains:
* a quick look up member for the common case
* a hash table which keeps per relation information
* a memory context that should be long lived enough and is
* responsible for reseting the state via its reset cb
*/
static struct AOCOLocal
{
AOCODMLState *last_used_state;
HTAB *dmlDescriptorTab;
MemoryContext stateCxt;
MemoryContextCallback cb;
} aocoLocal = {
.last_used_state = NULL,
.dmlDescriptorTab = NULL,
.stateCxt = NULL,
.cb = {
.func = reset_state_cb,
.arg = NULL
},
};
/*
* There are two cases that we are called from, during context destruction
* after a successful completion and after a transaction abort. Only in the
* second case we should not have cleaned up the DML state and the entries in
* the hash table. We need to reset our global state. The actual clean up is
* taken care elsewhere.
*/
static void
reset_state_cb(void *arg)
{
aocoLocal.dmlDescriptorTab = NULL;
aocoLocal.last_used_state = NULL;
aocoLocal.stateCxt = NULL;
}
static void
init_dml_local_state(void)
{
HASHCTL hash_ctl;
if (!aocoLocal.dmlDescriptorTab)
{
Assert(aocoLocal.stateCxt == NULL);
aocoLocal.stateCxt = AllocSetContextCreate(
CurrentMemoryContext,
"AppendOnly DML State Context",
ALLOCSET_SMALL_SIZES);
MemoryContextRegisterResetCallback(
aocoLocal.stateCxt,
&aocoLocal.cb);
memset(&hash_ctl, 0, sizeof(hash_ctl));
hash_ctl.keysize = sizeof(Oid);
hash_ctl.entrysize = sizeof(AOCODMLState);
hash_ctl.hcxt = aocoLocal.stateCxt;
aocoLocal.dmlDescriptorTab =
hash_create("AppendOnly DML state", 128, &hash_ctl,
HASH_CONTEXT | HASH_ELEM | HASH_BLOBS);
}
}
/*
* Create and insert a state entry for a relation. The actual descriptors will
* be created lazily when/if needed.
*
* Should be called exactly once per relation.
*/
static inline AOCODMLState *
enter_dml_state(const Oid relationOid)
{
AOCODMLState *state;
bool found;
Assert(aocoLocal.dmlDescriptorTab);
state = (AOCODMLState *) hash_search(
aocoLocal.dmlDescriptorTab,
&relationOid,
HASH_ENTER,
&found);
Assert(!found);
state->insertDesc = NULL;
state->deleteDesc = NULL;
aocoLocal.last_used_state = state;
return state;
}
/*
* Retrieve the state information for a relation.
* It is required that the state has been created before hand.
*/
static inline AOCODMLState *
find_dml_state(const Oid relationOid)
{
AOCODMLState *state;
Assert(aocoLocal.dmlDescriptorTab);
if (aocoLocal.last_used_state &&
aocoLocal.last_used_state->relationOid == relationOid)
return aocoLocal.last_used_state;
state = (AOCODMLState *) hash_search(
aocoLocal.dmlDescriptorTab,
&relationOid,
HASH_FIND,
NULL);
Assert(state);
aocoLocal.last_used_state = state;
return state;
}
/*
* Remove the state information for a relation.
* It is required that the state has been created before hand.
*
* Should be called exactly once per relation.
*/
static inline AOCODMLState *
remove_dml_state(const Oid relationOid)
{
AOCODMLState *state;
Assert(aocoLocal.dmlDescriptorTab);
state = (AOCODMLState *) hash_search(
aocoLocal.dmlDescriptorTab,
&relationOid,
HASH_REMOVE,
NULL);
Assert(state);
if (aocoLocal.last_used_state &&
aocoLocal.last_used_state->relationOid == relationOid)
aocoLocal.last_used_state = NULL;
return state;
}
/*
* Although the operation param is superfluous at the momment, the signature of
* the function is such for balance between the init and finish.
*
* This function should be called exactly once per relation.
*/
void
aoco_dml_init(Relation relation, CmdType operation)
{
init_dml_local_state();
(void) enter_dml_state(RelationGetRelid(relation));
}
/*
* This function should be called exactly once per relation.
*/
void
aoco_dml_finish(Relation relation, CmdType operation)
{
AOCODMLState *state;
state = remove_dml_state(RelationGetRelid(relation));
if (state->deleteDesc)
{
aocs_delete_finish(state->deleteDesc);
state->deleteDesc = NULL;
/*
* Bump up the modcount. If we inserted something (meaning that
* this was an UPDATE), we can skip this, as the insertion bumped
* up the modcount already.
*/
if (!state->insertDesc)
AORelIncrementModCount(relation);
}
if (state->insertDesc)
{
Assert(state->insertDesc->aoi_rel == relation);
aocs_insert_finish(state->insertDesc);
state->insertDesc = NULL;
}
}
/*
* Retrieve the insertDescriptor for a relation. Initialize it if needed.
*/
static AOCSInsertDesc
get_insert_descriptor(const Relation relation)
{
AOCODMLState *state;
state = find_dml_state(RelationGetRelid(relation));
if (state->insertDesc == NULL)
{
MemoryContext oldcxt;
oldcxt = MemoryContextSwitchTo(aocoLocal.stateCxt);
state->insertDesc = aocs_insert_init(relation,
ChooseSegnoForWrite(relation));
MemoryContextSwitchTo(oldcxt);
}
return state->insertDesc;
}
/*
* Retrieve the deleteDescriptor for a relation. Initialize it if needed.
*/
static AOCSDeleteDesc
get_delete_descriptor(const Relation relation, bool forUpdate)
{
AOCODMLState *state;
state = find_dml_state(RelationGetRelid(relation));
if (state->deleteDesc == NULL)
{
/*
* GPDB_12_MERGE_FIXME: Can we perform this check earlier on?
* Example during init? Idealy should be called on master node first,
* that way we will avoid the dispatch.
*/
MemoryContext oldcxt;
if (IsolationUsesXactSnapshot())
{
if (forUpdate)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("updates on append-only tables are not supported in serializable transactions")));
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("deletes on append-only tables are not supported in serializable transactions")));
}
oldcxt = MemoryContextSwitchTo(aocoLocal.stateCxt);
state->deleteDesc = aocs_delete_init(relation);
MemoryContextSwitchTo(oldcxt);
}
return state->deleteDesc;
}
/*
* AO_COLUMN access method uses virtual tuples
*/
static const TupleTableSlotOps *
aoco_slot_callbacks(Relation relation)
{
return &TTSOpsVirtual;
}
struct ExtractcolumnContext
{
bool *cols;
AttrNumber natts;
bool found;
};
static bool
extractcolumns_walker(Node *node, struct ExtractcolumnContext *ecCtx)
{
if (node == NULL)
return false;
if (IsA(node, Var))
{
Var *var = (Var *)node;
if (IS_SPECIAL_VARNO(var->varno))
return false;
if (var->varattno > 0 && var->varattno <= ecCtx->natts)
{
ecCtx->cols[var->varattno -1] = true;
ecCtx->found = true;
}
/*
* If all attributes are included,
* set all entries in mask to true.
*/
else if (var->varattno == 0)
{
for (AttrNumber attno = 0; attno < ecCtx->natts; attno++)
ecCtx->cols[attno] = true;
ecCtx->found = true;
return true;
}
return false;
}
return expression_tree_walker(node, extractcolumns_walker, (void *)ecCtx);
}
static bool
extractcolumns_from_node(Node *expr, bool *cols, AttrNumber natts)
{
struct ExtractcolumnContext ecCtx;
ecCtx.cols = cols;
ecCtx.natts = natts;
ecCtx.found = false;
extractcolumns_walker(expr, &ecCtx);
return ecCtx.found;
}
static TableScanDesc
aoco_beginscan_extractcolumns(Relation rel, Snapshot snapshot,
List *targetlist, List *qual,
uint32 flags)
{
AOCSScanDesc aoscan;
AttrNumber natts = RelationGetNumberOfAttributes(rel);
bool *cols;
bool found = false;
cols = palloc0(natts * sizeof(*cols));
found |= extractcolumns_from_node((Node *)targetlist, cols, natts);
found |= extractcolumns_from_node((Node *)qual, cols, natts);
/*
* In some cases (for example, count(*)), targetlist and qual may be null,
* extractcolumns_walker will return immediately, so no columns are specified.
* We always scan the first column.
*/
if (!found)
cols[0] = true;
aoscan = aocs_beginscan(rel,
snapshot,
cols,
flags);
pfree(cols);
return (TableScanDesc)aoscan;
}
static TableScanDesc
aoco_beginscan_extractcolumns_bm(Relation rel, Snapshot snapshot,
List *targetlist, List *qual,
List *bitmapqualorig,
uint32 flags)
{
AOCSBitmapScan aocsBitmapScan;
AttrNumber natts = RelationGetNumberOfAttributes(rel);
bool *proj;
bool *projRecheck;
bool found;
aocsBitmapScan = palloc0(sizeof(*aocsBitmapScan));
aocsBitmapScan->descIdentifier = AOCSBITMAPSCANDATA;
aocsBitmapScan->rs_base.rs_rd = rel;
aocsBitmapScan->rs_base.rs_snapshot = snapshot;
aocsBitmapScan->rs_base.rs_flags = flags;
proj = palloc0(natts * sizeof(*proj));
projRecheck = palloc0(natts * sizeof(*projRecheck));
if (snapshot == SnapshotAny)
aocsBitmapScan->appendOnlyMetaDataSnapshot = GetTransactionSnapshot();
else
aocsBitmapScan->appendOnlyMetaDataSnapshot = snapshot;
found = extractcolumns_from_node((Node *)targetlist, proj, natts);
found |= extractcolumns_from_node((Node *)qual, proj, natts);
memcpy(projRecheck, proj, natts * sizeof(*projRecheck));
if (extractcolumns_from_node((Node *)bitmapqualorig, projRecheck, natts))
{
/*
* At least one column needs to be projected in non-recheck case.
* Otherwise, the AO_COLUMN fetch code may skip visimap checking because
* there are no columns to be scanned and we may get wrong results.
*/
if (!found)
proj[0] = true;
}
else if (!found)
{
/* XXX can we have no columns to project at all? */
proj[0] = projRecheck[0] = true;
}
aocsBitmapScan->bitmapScanDesc[NO_RECHECK].proj = proj;
aocsBitmapScan->bitmapScanDesc[RECHECK].proj = projRecheck;
return (TableScanDesc)aocsBitmapScan;
}
/*
* This function intentionally ignores key and nkeys
*/
static TableScanDesc
aoco_beginscan(Relation relation,
Snapshot snapshot,
int nkeys, struct ScanKeyData *key,
ParallelTableScanDesc pscan,
uint32 flags)
{
AOCSScanDesc aoscan;
/* Parallel scan not supported for AO_COLUMN tables */
Assert(pscan == NULL);
aoscan = aocs_beginscan(relation,
snapshot,
NULL,
flags);
return (TableScanDesc) aoscan;
}
static void
aoco_endscan(TableScanDesc scan)
{
AOCSScanDesc aocsScanDesc;
AOCSBitmapScan aocsBitmapScan;
aocsScanDesc = (AOCSScanDesc) scan;
if (aocsScanDesc->descIdentifier == AOCSSCANDESCDATA)
{
aocs_endscan(aocsScanDesc);
return;
}
Assert(aocsScanDesc->descIdentifier == AOCSBITMAPSCANDATA);
aocsBitmapScan = (AOCSBitmapScan) scan;
if (aocsBitmapScan->bitmapScanDesc[NO_RECHECK].bitmapFetch)
aocs_fetch_finish(aocsBitmapScan->bitmapScanDesc[NO_RECHECK].bitmapFetch);
if (aocsBitmapScan->bitmapScanDesc[RECHECK].bitmapFetch)
aocs_fetch_finish(aocsBitmapScan->bitmapScanDesc[RECHECK].bitmapFetch);
pfree(aocsBitmapScan->bitmapScanDesc[NO_RECHECK].proj);
pfree(aocsBitmapScan->bitmapScanDesc[RECHECK].proj);
}
static void
aoco_rescan(TableScanDesc scan, ScanKey key,
bool set_params, bool allow_strat,
bool allow_sync, bool allow_pagemode)
{
AOCSScanDesc aoscan = (AOCSScanDesc) scan;
if (aoscan->descIdentifier == AOCSSCANDESCDATA)
aocs_rescan(aoscan);
}
static bool
aoco_getnextslot(TableScanDesc scan, ScanDirection direction, TupleTableSlot *slot)
{
AOCSScanDesc aoscan = (AOCSScanDesc)scan;
ExecClearTuple(slot);
if (aocs_getnext(aoscan, direction, slot))
{
ExecStoreVirtualTuple(slot);
pgstat_count_heap_getnext(aoscan->rs_base.rs_rd);
return true;
}
return false;
}
static Size
aoco_parallelscan_estimate(Relation rel)
{
elog(ERROR, "parallel SeqScan not implemented for AO_COLUMN tables");
}
static Size
aoco_parallelscan_initialize(Relation rel, ParallelTableScanDesc pscan)
{
elog(ERROR, "parallel SeqScan not implemented for AO_COLUMN tables");
}
static void
aoco_parallelscan_reinitialize(Relation rel, ParallelTableScanDesc pscan)
{
elog(ERROR, "parallel SeqScan not implemented for AO_COLUMN tables");
}
static IndexFetchTableData *
aoco_index_fetch_begin(Relation rel)
{
IndexFetchAOCOData *aocoscan = palloc0(sizeof(IndexFetchAOCOData));
aocoscan->xs_base.rel = rel;
/* aocoscan other variables are initialized lazily on first fetch */
return &aocoscan->xs_base;
}
static void
aoco_index_fetch_reset(IndexFetchTableData *scan)
{
/*
* Unlike Heap, we don't release the resources (fetch descriptor and its
* members) here because it is more like a global data structure shared
* across scans, rather than an iterator to yield a granularity of data.
*
* Additionally, should be aware of that no matter whether allocation or
* release on fetch descriptor, it is considerably expensive.
*/
return;
}
static void
aoco_index_fetch_end(IndexFetchTableData *scan)
{
IndexFetchAOCOData *aocoscan = (IndexFetchAOCOData *) scan;
if (aocoscan->aocofetch)
{
aocs_fetch_finish(aocoscan->aocofetch);
pfree(aocoscan->aocofetch);
aocoscan->aocofetch = NULL;
}
if (aocoscan->proj)
{
pfree(aocoscan->proj);
aocoscan->proj = NULL;
}
pfree(aocoscan);
}
static bool
aoco_index_fetch_tuple(struct IndexFetchTableData *scan,
ItemPointer tid,
Snapshot snapshot,
TupleTableSlot *slot,
bool *call_again, bool *all_dead)
{
IndexFetchAOCOData *aocoscan = (IndexFetchAOCOData *) scan;
if (!aocoscan->aocofetch)
{
Snapshot appendOnlyMetaDataSnapshot;
int natts;
/* Initiallize the projection info, assumes the whole row */
Assert(!aocoscan->proj);
natts = RelationGetNumberOfAttributes(scan->rel);
aocoscan->proj = palloc(natts * sizeof(*aocoscan->proj));
MemSet(aocoscan->proj, true, natts * sizeof(*aocoscan->proj));
appendOnlyMetaDataSnapshot = snapshot;
if (appendOnlyMetaDataSnapshot == SnapshotAny)
{
/*
* the append-only meta data should never be fetched with
* SnapshotAny as bogus results are returned.
*/
appendOnlyMetaDataSnapshot = GetTransactionSnapshot();
}
aocoscan->aocofetch = aocs_fetch_init(aocoscan->xs_base.rel,
snapshot,
appendOnlyMetaDataSnapshot,
aocoscan->proj);
}
/*
* There is no reason to expect changes on snapshot between tuple
* fetching calls after fech_init is called, treat it as a
* programming error in case of occurrence.
*/
Assert(aocoscan->aocofetch->snapshot == snapshot);
ExecClearTuple(slot);
if (aocs_fetch(aocoscan->aocofetch, (AOTupleId *) tid, slot))
{
ExecStoreVirtualTuple(slot);
return true;
}
return false;
}
static void
aoco_tuple_insert(Relation relation, TupleTableSlot *slot, CommandId cid,
int options, BulkInsertState bistate)
{
AOCSInsertDesc insertDesc;
insertDesc = get_insert_descriptor(relation);
aocs_insert(insertDesc, slot);
pgstat_count_heap_insert(relation, 1);
}
static void
aoco_tuple_insert_speculative(Relation relation, TupleTableSlot *slot,
CommandId cid, int options,
BulkInsertState bistate, uint32 specToken)
{
/* GPDB_12_MERGE_FIXME: not supported. Can this function be left out completely? Or ereport()? */
elog(ERROR, "speculative insertion not supported on AO_COLUMN tables");
}
static void
aoco_tuple_complete_speculative(Relation relation, TupleTableSlot *slot,
uint32 specToken, bool succeeded)
{
elog(ERROR, "speculative insertion not supported on AO_COLUMN tables");
}
/*
* aoco_multi_insert - insert multiple tuples into an ao relation
*
* This is like aoco_tuple_insert(), but inserts multiple tuples in one
* operation. Typicaly used by COPY. This is preferrable than calling
* aoco_tuple_insert() in a loop because ... WAL??
*/
static void
aoco_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
CommandId cid, int options, BulkInsertState bistate)
{
/*
* GPDB_12_MERGE_FIXME: Poor man's implementation for now in order to make
* the tests pass. Implement properly.
*/
for (int i = 0; i < ntuples; i++)
aoco_tuple_insert(relation, slots[i], cid, options, bistate);
}
static TM_Result
aoco_tuple_delete(Relation relation, ItemPointer tid, CommandId cid,
Snapshot snapshot, Snapshot crosscheck, bool wait,
TM_FailureData *tmfd, bool changingPart)
{
AOCSDeleteDesc deleteDesc;
TM_Result result;
deleteDesc = get_delete_descriptor(relation, false);
result = aocs_delete(deleteDesc, (AOTupleId *) tid);
if (result == TM_Ok)
pgstat_count_heap_delete(relation);
else if (result == TM_SelfModified)
{
/*
* The visibility map entry has been set and it was in this command.
*
* Our caller might want to investigate tmfd to decide on appropriate
* action. Set it here to match expectations. The uglyness here is
* preferrable to having to inspect the relation's am in the caller.
*/
tmfd->cmax = cid;
}
return result;
}
static TM_Result
aoco_tuple_update(Relation relation, ItemPointer otid, TupleTableSlot *slot,
CommandId cid, Snapshot snapshot, Snapshot crosscheck,
bool wait, TM_FailureData *tmfd,
LockTupleMode *lockmode, bool *update_indexes)
{
AOCSInsertDesc insertDesc;
AOCSDeleteDesc deleteDesc;
TM_Result result;
insertDesc = get_insert_descriptor(relation);
deleteDesc = get_delete_descriptor(relation, true);
/* Update the tuple with table oid */
slot->tts_tableOid = RelationGetRelid(relation);
#ifdef FAULT_INJECTOR
FaultInjector_InjectFaultIfSet(
"appendonly_update",
DDLNotSpecified,
"", //databaseName
RelationGetRelationName(insertDesc->aoi_rel));
/* tableName */
#endif
result = aocs_delete(deleteDesc, (AOTupleId *) otid);
if (result != TM_Ok)
return result;
aocs_insert(insertDesc, slot);
pgstat_count_heap_update(relation, false);
/* No HOT updates with AO tables. */
*update_indexes = true;
return result;
}
static TM_Result
aoco_tuple_lock(Relation relation, ItemPointer tid, Snapshot snapshot,
TupleTableSlot *slot, CommandId cid, LockTupleMode mode,
LockWaitPolicy wait_policy, uint8 flags,
TM_FailureData *tmfd)
{
/* GPDB_12_MERGE_FIXME: not supported. Can this function be left out completely? Or ereport()? */
elog(ERROR, "speculative insertion not supported on AO tables");
}
static void
aoco_finish_bulk_insert(Relation relation, int options)
{
aoco_dml_finish(relation, CMD_INSERT);
}
/* ------------------------------------------------------------------------
* Callbacks for non-modifying operations on individual tuples for heap AM
* ------------------------------------------------------------------------
*/
static bool
aoco_fetch_row_version(Relation relation,
ItemPointer tid,
Snapshot snapshot,
TupleTableSlot *slot)
{
/*
* This is a generic interface. It is currently used in three distinct
* cases, only one of which is currently invoking it for AO tables.
* This is DELETE RETURNING. In order to return the slot via the tid for
* AO tables one would have to scan the block directory and the visibility
* map. A block directory is not guarranteed to exist. Even if it exists, a
* state would have to be created and dropped for every tuple look up since
* this interface does not allow for the state to be passed around. This is
* a very costly operation to be performed per tuple lookup. Furthermore, if
* a DELETE operation is currently on the fly, the corresponding visibility
* map entries will not have been finalized into a visibility map tuple.
*
* Error out with feature not supported. Given that this is a generic
* interface, we can not really say which feature is that, although we do
* know that is DELETE RETURNING.
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("feature not supported on appendoptimized relations")));
}
static void
aoco_get_latest_tid(TableScanDesc sscan,
ItemPointer tid)
{
/*
* Tid scans are not supported for appendoptimized relation. This function
* should not have been called in the first place, but if it is called,
* better to error out.
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("feature not supported on appendoptimized relations")));
}
static bool
aoco_tuple_tid_valid(TableScanDesc scan, ItemPointer tid)
{
/*
* Tid scans are not supported for appendoptimized relation. This function
* should not have been called in the first place, but if it is called,
* better to error out.
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("feature not supported on appendoptimized relations")));
}
static bool
aoco_tuple_satisfies_snapshot(Relation rel, TupleTableSlot *slot,
Snapshot snapshot)
{
/*
* AO_COLUMN table dose not support unique and tidscan yet.
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("feature not supported on appendoptimized relations")));
}
static TransactionId
aoco_compute_xid_horizon_for_tuples(Relation rel,
ItemPointerData *tids,
int nitems)
{
// GPDB_12_MERGE_FIXME: vacuum related call back.
elog(ERROR, "not implemented yet");
}
/* ------------------------------------------------------------------------
* DDL related callbacks for ao_column AM.
* ------------------------------------------------------------------------
*/
static void
aoco_relation_set_new_filenode(Relation rel,
const RelFileNode *newrnode,
char persistence,
TransactionId *freezeXid,
MultiXactId *minmulti)
{
SMgrRelation srel;
/*
* Append-optimized tables do not contain transaction information in
* tuples.
*/
*freezeXid = *minmulti = InvalidTransactionId;
/*
* No special treatment is needed for new AO_ROW/COLUMN relation. Create
* the underlying disk file storage for the relation. No clean up is
* needed, RelationCreateStorage() is transactional.
*
* Segment files will be created when / if needed.
*/
srel = RelationCreateStorage(*newrnode, persistence, SMGR_AO);
/*
* If required, set up an init fork for an unlogged table so that it can
* be correctly reinitialized on restart. An immediate sync is required
* even if the page has been logged, because the write did not go through
* shared_buffers and therefore a concurrent checkpoint may have moved the
* redo pointer past our xlog record. Recovery may as well remove it
* while replaying, for example, XLOG_DBASE_CREATE or XLOG_TBLSPC_CREATE
* record. Therefore, logging is necessary even if wal_level=minimal.
*/
if (persistence == RELPERSISTENCE_UNLOGGED)
{
Assert(rel->rd_rel->relkind == RELKIND_RELATION ||
rel->rd_rel->relkind == RELKIND_MATVIEW ||
rel->rd_rel->relkind == RELKIND_TOASTVALUE);
smgrcreate(srel, INIT_FORKNUM, false);
log_smgrcreate(newrnode, INIT_FORKNUM, SMGR_AO);
smgrimmedsync(srel, INIT_FORKNUM);
}
smgrclose(srel);
}
/* helper routine to call open a rel and call heap_truncate_one_rel() on it */
static void
heap_truncate_one_relid(Oid relid)
{
if (OidIsValid(relid))
{
Relation rel = relation_open(relid, AccessExclusiveLock);
heap_truncate_one_rel(rel);
relation_close(rel, NoLock);
}
}
static void
aoco_relation_nontransactional_truncate(Relation rel)
{
Oid ao_base_relid = RelationGetRelid(rel);
Oid aoseg_relid = InvalidOid;
Oid aoblkdir_relid = InvalidOid;
Oid aovisimap_relid = InvalidOid;
ao_truncate_one_rel(rel);
/* Also truncate the aux tables */
GetAppendOnlyEntryAuxOids(ao_base_relid, NULL,
&aoseg_relid,
&aoblkdir_relid, NULL,
&aovisimap_relid, NULL);
heap_truncate_one_relid(aoseg_relid);
heap_truncate_one_relid(aoblkdir_relid);
heap_truncate_one_relid(aovisimap_relid);
}
static void
aoco_relation_copy_data(Relation rel, const RelFileNode *newrnode)
{
SMgrRelation dstrel;
/*
* Use the "AO-specific" (non-shared buffers backed storage) SMGR
* implementation
*/
dstrel = smgropen(*newrnode, rel->rd_backend, SMGR_AO);
RelationOpenSmgr(rel);
/*
* Create and copy all forks of the relation, and schedule unlinking of
* old physical files.
*
* NOTE: any conflict in relfilenode value will be caught in
* RelationCreateStorage().
*/
RelationCreateStorage(*newrnode, rel->rd_rel->relpersistence, SMGR_AO);
copy_append_only_data(rel->rd_node, *newrnode, rel->rd_backend, rel->rd_rel->relpersistence);
/*
* For append-optimized tables, no forks other than the main fork should
* exist with the exception of unlogged tables. For unlogged AO tables,
* INIT_FORK must exist.
*/
if (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED)
{
Assert (smgrexists(rel->rd_smgr, INIT_FORKNUM));
/*
* INIT_FORK is empty, creating it is sufficient, no need to copy
* contents from source to destination.
*/
smgrcreate(dstrel, INIT_FORKNUM, false);
log_smgrcreate(newrnode, INIT_FORKNUM, SMGR_AO);
}
/* drop old relation, and close new one */
RelationDropStorage(rel);
smgrclose(dstrel);
}
static void
aoco_vacuum_rel(Relation onerel, VacuumParams *params,
BufferAccessStrategy bstrategy)
{
/*
* Implemented but not invoked, we do the AO_COLUMN different phases vacuuming by
* calling ao_vacuum_rel() in vacuum_rel() directly for now.
*/
ao_vacuum_rel(onerel, params, bstrategy);
return;
}
static void
aoco_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
Relation OldIndex, bool use_sort,
TransactionId OldestXmin,
TransactionId *xid_cutoff,
MultiXactId *multi_cutoff,
double *num_tuples,
double *tups_vacuumed,
double *tups_recently_dead)
{
TupleDesc oldTupDesc;
TupleDesc newTupDesc;
int natts;
Datum *values;
bool *isnull;
TransactionId FreezeXid;
MultiXactId MultiXactCutoff;
Tuplesortstate *tuplesort;
PGRUsage ru0;
AOTupleId aoTupleId;
AOCSInsertDesc idesc = NULL;
int write_seg_no;
AOCSScanDesc scan = NULL;
TupleTableSlot *slot;
pg_rusage_init(&ru0);
/*
* Curently AO storage lacks cost model for IndexScan, thus IndexScan
* is not functional. In future, probably, this will be fixed and CLUSTER
* command will support this. Though, random IO over AO on TID stream
* can be impractical anyway.
* Here we are sorting data on on the lines of heap tables, build a tuple
* sort state and sort the entire AO table using the index key, rewrite
* the table, one tuple at a time, in order as returned by tuple sort state.
*/
if (OldIndex == NULL || !IS_BTREE(OldIndex))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot cluster append-optimized table \"%s\"", RelationGetRelationName(OldHeap)),
errdetail("Append-optimized tables can only be clustered against a B-tree index")));
/*
* Their tuple descriptors should be exactly alike, but here we only need
* assume that they have the same number of columns.
*/
oldTupDesc = RelationGetDescr(OldHeap);
newTupDesc = RelationGetDescr(NewHeap);
Assert(newTupDesc->natts == oldTupDesc->natts);
/* Preallocate values/isnull arrays to deform heap tuples after sort */
natts = newTupDesc->natts;
values = (Datum *) palloc(natts * sizeof(Datum));
isnull = (bool *) palloc(natts * sizeof(bool));
/*
* If the OldHeap has a toast table, get lock on the toast table to keep
* it from being vacuumed. This is needed because autovacuum processes
* toast tables independently of their main tables, with no lock on the
* latter. If an autovacuum were to start on the toast table after we
* compute our OldestXmin below, it would use a later OldestXmin, and then
* possibly remove as DEAD toast tuples belonging to main tuples we think
* are only RECENTLY_DEAD. Then we'd fail while trying to copy those
* tuples.
*
* We don't need to open the toast relation here, just lock it. The lock
* will be held till end of transaction.
*/
if (OldHeap->rd_rel->reltoastrelid)
LockRelationOid(OldHeap->rd_rel->reltoastrelid, AccessExclusiveLock);
/* use_wal off requires smgr_targblock be initially invalid */
Assert(RelationGetTargetBlock(NewHeap) == InvalidBlockNumber);
/*
* Compute sane values for FreezeXid and CutoffMulti with regular
* VACUUM machinery to avoidconfising existing CLUSTER code.
*/
vacuum_set_xid_limits(OldHeap, 0, 0, 0, 0,
&OldestXmin, &FreezeXid, NULL, &MultiXactCutoff,
NULL);
/*
* FreezeXid will become the table's new relfrozenxid, and that mustn't go
* backwards, so take the max.
*/
if (TransactionIdPrecedes(FreezeXid, OldHeap->rd_rel->relfrozenxid))
FreezeXid = OldHeap->rd_rel->relfrozenxid;
/*
* MultiXactCutoff, similarly, shouldn't go backwards either.
*/
if (MultiXactIdPrecedes(MultiXactCutoff, OldHeap->rd_rel->relminmxid))
MultiXactCutoff = OldHeap->rd_rel->relminmxid;
/* return selected values to caller */
*xid_cutoff = FreezeXid;
*multi_cutoff = MultiXactCutoff;
tuplesort = tuplesort_begin_cluster(oldTupDesc, OldIndex,
maintenance_work_mem, NULL, false);
/* Log what we're doing */
ereport(DEBUG2,
(errmsg("clustering \"%s.%s\" using sequential scan and sort",
get_namespace_name(RelationGetNamespace(OldHeap)),
RelationGetRelationName(OldHeap))));
/* Scan through old table to convert data into tuples for sorting */
slot = table_slot_create(OldHeap, NULL);
scan = aocs_beginscan(OldHeap, GetActiveSnapshot(),
NULL /* proj */,
0 /* flags */);
while (aocs_getnext(scan, ForwardScanDirection, slot))
{
Datum *slot_values;
bool *slot_isnull;
HeapTuple tuple;
CHECK_FOR_INTERRUPTS();
slot_getallattrs(slot);
slot_values = slot->tts_values;
slot_isnull = slot->tts_isnull;
tuple = heap_form_tuple(oldTupDesc, slot_values, slot_isnull);
*num_tuples += 1;
tuplesort_putheaptuple(tuplesort, tuple);
heap_freetuple(tuple);
}
ExecDropSingleTupleTableSlot(slot);
aocs_endscan(scan);
/*
* Сomplete the sort, then read out all tuples
* from the tuplestore and write them to the new relation.
*/
tuplesort_performsort(tuplesort);
write_seg_no = ChooseSegnoForWrite(NewHeap);
idesc = aocs_insert_init(NewHeap, write_seg_no);
/* Insert sorted heap tuples into new storage */
for (;;)
{
HeapTuple tuple;
CHECK_FOR_INTERRUPTS();
tuple = tuplesort_getheaptuple(tuplesort, true);
if (tuple == NULL)
break;
heap_deform_tuple(tuple, oldTupDesc, values, isnull);
aocs_insert_values(idesc, values, isnull, &aoTupleId);
}
tuplesort_end(tuplesort);
/* Finish and deallocate insertion */
aocs_insert_finish(idesc);
}
static bool
aoco_scan_analyze_next_block(TableScanDesc scan, BlockNumber blockno,
BufferAccessStrategy bstrategy)
{
AOCSScanDesc aoscan = (AOCSScanDesc) scan;
aoscan->targetTupleId = blockno;
return true;
}
static bool
aoco_scan_analyze_next_tuple(TableScanDesc scan, TransactionId OldestXmin,
double *liverows, double *deadrows,
TupleTableSlot *slot)
{
AOCSScanDesc aoscan = (AOCSScanDesc) scan;
bool ret = false;
/* skip several tuples if they are not sampling target */
while (aoscan->targetTupleId > aoscan->nextTupleId)
{
aoco_getnextslot(scan, ForwardScanDirection, slot);
aoscan->nextTupleId++;
}
if (aoscan->targetTupleId == aoscan->nextTupleId)
{
ret = aoco_getnextslot(scan, ForwardScanDirection, slot);
aoscan->nextTupleId++;
if (ret)
*liverows += 1;
else
*deadrows += 1; /* if return an invisible tuple */
}
return ret;
}
static double
aoco_index_build_range_scan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
bool anyvisible,
bool progress,
BlockNumber start_blockno,
BlockNumber numblocks,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan)
{
AOCSScanDesc aocoscan;
bool is_system_catalog;
bool checking_uniqueness;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
double reltuples;
ExprState *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
Snapshot snapshot;
bool need_unregister_snapshot = false;
bool need_create_blk_directory = false;
List *tlist = NIL;
List *qual = indexInfo->ii_Predicate;
Oid blkdirrelid;
Oid blkidxrelid;
TransactionId OldestXmin;
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/* Remember if it's a system catalog */
is_system_catalog = IsSystemRelation(heapRelation);
/* Appendoptimized catalog tables are not supported. */
Assert(!is_system_catalog);
/* Appendoptimized tables have no data on master. */
if (IS_QUERY_DISPATCHER())
return 0;
/* See whether we're verifying uniqueness/exclusion properties */
checking_uniqueness = (indexInfo->ii_Unique ||
indexInfo->ii_ExclusionOps != NULL);
/*
* "Any visible" mode is not compatible with uniqueness checks; make sure
* only one of those is requested.
*/
Assert(!(anyvisible && checking_uniqueness));
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = table_slot_create(heapRelation, NULL);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
/*
* Prepare for scan of the base relation. In a normal index build, we use
* SnapshotAny because we must retrieve all tuples and do our own time
* qual checks (because we have to index RECENTLY_DEAD tuples). In a
* concurrent build, or during bootstrap, we take a regular MVCC snapshot
* and index whatever's live according to that.
*/
OldestXmin = InvalidTransactionId;
/* okay to ignore lazy VACUUMs here */
if (!IsBootstrapProcessingMode() && !indexInfo->ii_Concurrent)
OldestXmin = GetOldestXmin(heapRelation, PROCARRAY_FLAGS_VACUUM);
/*
* If block directory is empty, it must also be built along with the index.
*/
GetAppendOnlyEntryAuxOids(RelationGetRelid(heapRelation), NULL, NULL,
&blkdirrelid, &blkidxrelid, NULL, NULL);
Relation blkdir = relation_open(blkdirrelid, AccessShareLock);
need_create_blk_directory = RelationGetNumberOfBlocks(blkdir) == 0;
relation_close(blkdir, NoLock);
if (!scan)
{
/*
* Serial index build.
*
* Must begin our own heap scan in this case. We may also need to
* register a snapshot whose lifetime is under our direct control.
*/
if (!TransactionIdIsValid(OldestXmin))
{
snapshot = RegisterSnapshot(GetTransactionSnapshot());
need_unregister_snapshot = true;
}
else
snapshot = SnapshotAny;
/*
* Scan all columns if we need to create block directory.
*/
if (need_create_blk_directory)
{
scan = table_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
allow_sync); /* syncscan OK? */
}
else
{
/*
* if block directory has created, we can only scan needed column.
*/
for (int i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
AttrNumber attrnum = indexInfo->ii_IndexAttrNumbers[i];
Form_pg_attribute attr = TupleDescAttr(RelationGetDescr(heapRelation), attrnum - 1);
Var *var = makeVar(i,
attrnum,
attr->atttypid,
attr->atttypmod,
attr->attcollation,
0);
/* Build a target list from index info */
tlist = lappend(tlist,
makeTargetEntry((Expr *) var,
list_length(tlist) + 1,
NULL,
false));
}
/* Push down target list and qual to scan */
scan = table_beginscan_es(heapRelation, /* relation */
snapshot, /* snapshot */
tlist, /* targetlist */
qual); /* qual */
}
}
else
{
/*
* Parallel index build.
*
* Parallel case never registers/unregisters own snapshot. Snapshot
* is taken from parallel heap scan, and is SnapshotAny or an MVCC
* snapshot, based on same criteria as serial case.
*/
Assert(!IsBootstrapProcessingMode());
Assert(allow_sync);
snapshot = scan->rs_snapshot;
}
aocoscan = (AOCSScanDesc) scan;
/*
* Note that block directory is created during creation of the first
* index. If it is found empty, it means the block directory was created
* by this create index transaction. The caller (DefineIndex) must have
* acquired sufficiently strong lock on the appendoptimized table such
* that index creation as well as insert from concurrent transactions are
* blocked. We can rest assured of exclusive access to the block
* directory relation.
*/
if (need_create_blk_directory)
{
/*
* Allocate blockDirectory in scan descriptor to let the access method
* know that it needs to also build the block directory while
* scanning.
*/
Assert(aocoscan->blockDirectory == NULL);
aocoscan->blockDirectory = palloc0(sizeof(AppendOnlyBlockDirectory));
}
/* GPDB_12_MERGE_FIXME */
#if 0
/* Publish number of blocks to scan */
if (progress)
{
BlockNumber nblocks;
if (aoscan->rs_base.rs_parallel != NULL)
{
ParallelBlockTableScanDesc pbscan;
pbscan = (ParallelBlockTableScanDesc) aoscan->rs_base.rs_parallel;
nblocks = pbscan->phs_nblocks;
}
else
nblocks = aoscan->rs_nblocks;
pgstat_progress_update_param(PROGRESS_SCAN_BLOCKS_TOTAL,
nblocks);
}
#endif
/*
* Must call GetOldestXmin() with SnapshotAny. Should never call
* GetOldestXmin() with MVCC snapshot. (It's especially worth checking
* this for parallel builds, since ambuild routines that support parallel
* builds must work these details out for themselves.)
*/
Assert(snapshot == SnapshotAny || IsMVCCSnapshot(snapshot));
Assert(snapshot == SnapshotAny ? TransactionIdIsValid(OldestXmin) :
!TransactionIdIsValid(OldestXmin));
Assert(snapshot == SnapshotAny || !anyvisible);
/* set our scan endpoints */
if (!allow_sync)
{
}
else
{
/* syncscan can only be requested on whole relation */
Assert(start_blockno == 0);
Assert(numblocks == InvalidBlockNumber);
}
reltuples = 0;
/*
* Scan all tuples in the base relation.
*/
while (aoco_getnextslot(&aocoscan->rs_base, ForwardScanDirection, slot))
{
bool tupleIsAlive;
CHECK_FOR_INTERRUPTS();
/*
* GPDB_12_MERGE_FIXME: How to properly do a partial scan? Currently,
* we scan the whole table, and throw away tuples that are not in the
* range. That's clearly very inefficient.
*/
if (ItemPointerGetBlockNumber(&slot->tts_tid) < start_blockno ||
(numblocks != InvalidBlockNumber && ItemPointerGetBlockNumber(&slot->tts_tid) >= numblocks))
continue;
/* GPDB_12_MERGE_FIXME */
#if 0
/* Report scan progress, if asked to. */
if (progress)
{
BlockNumber blocks_done = appendonly_scan_get_blocks_done(aoscan);
if (blocks_done != previous_blkno)
{
pgstat_progress_update_param(PROGRESS_SCAN_BLOCKS_DONE,
blocks_done);
previous_blkno = blocks_done;
}
}
#endif
/*
* appendonly_getnext did the time qual check
*
* GPDB_12_MERGE_FIXME: in heapam, we do visibility checks in SnapshotAny case
* here. Is that not needed with AO_COLUMN tables?
*/
tupleIsAlive = true;
reltuples += 1;
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NULL)
{
if (!ExecQual(predicate, econtext))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use in
* this index, and note which are null. This also performs evaluation
* of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* You'd think we should go ahead and build the index tuple here, but
* some index AMs want to do further processing on the data first. So
* pass the values[] and isnull[] arrays, instead.
*/
/* Call the AM's callback routine to process the tuple */
/*
* GPDB: the callback is modified to accept ItemPointer as argument
* instead of HeapTuple. That allows the callback to be reused for
* appendoptimized tables.
*/
callback(indexRelation, &slot->tts_tid, values, isnull, tupleIsAlive,
callback_state);
}
/* GPDB_12_MERGE_FIXME */
#if 0
/* Report scan progress one last time. */
if (progress)
{
BlockNumber blks_done;
if (aoscan->rs_base.rs_parallel != NULL)
{
ParallelBlockTableScanDesc pbscan;
pbscan = (ParallelBlockTableScanDesc) aoscan->rs_base.rs_parallel;
blks_done = pbscan->phs_nblocks;
}
else
blks_done = aoscan->rs_nblocks;
pgstat_progress_update_param(PROGRESS_SCAN_BLOCKS_DONE,
blks_done);
}
#endif
table_endscan(scan);
/* we can now forget our snapshot, if set and registered by us */
if (need_unregister_snapshot)
UnregisterSnapshot(snapshot);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NULL;
return reltuples;
}
static void
aoco_index_validate_scan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
Snapshot snapshot,
ValidateIndexState *state)
{
elog(ERROR, "not implemented yet");
}
/* ------------------------------------------------------------------------
* Miscellaneous callbacks for the heap AM
* ------------------------------------------------------------------------
*/
/*
* This pretends that the all the space is taken by the main fork.
* Returns the compressed size.
*/
static uint64
aoco_relation_size(Relation rel, ForkNumber forkNumber)
{
AOCSFileSegInfo **allseg;
Snapshot snapshot;
uint64 totalbytes = 0;
int totalseg;
if (forkNumber != MAIN_FORKNUM)
return totalbytes;
snapshot = RegisterSnapshot(GetLatestSnapshot());
allseg = GetAllAOCSFileSegInfo(rel, snapshot, &totalseg, NULL);
for (int seg = 0; seg < totalseg; seg++)
{
for (int attr = 0; attr < RelationGetNumberOfAttributes(rel); attr++)
{
AOCSVPInfoEntry *entry;
/*
* AWAITING_DROP segments might be missing information for some
* (newly-added) columns.
*/
if (attr < allseg[seg]->vpinfo.nEntry)
{
entry = getAOCSVPEntry(allseg[seg], attr);
/* Always return the compressed size */
totalbytes += entry->eof;
}
CHECK_FOR_INTERRUPTS();
}
}
if (allseg)
{
FreeAllAOCSSegFileInfo(allseg, totalseg);
pfree(allseg);
}
UnregisterSnapshot(snapshot);
return totalbytes;
}
static bool
aoco_relation_needs_toast_table(Relation rel)
{
/*
* AO_COLUMN never used the toasting, don't create the toast table from
* Greenplum 7
*/
return false;
}
/* ------------------------------------------------------------------------
* Planner related callbacks for the heap AM
* ------------------------------------------------------------------------
*/
static void
aoco_estimate_rel_size(Relation rel, int32 *attr_widths,
BlockNumber *pages, double *tuples,
double *allvisfrac)
{
FileSegTotals *fileSegTotals;
Snapshot snapshot;
*pages = 1;
*tuples = 1;
*allvisfrac = 0;
if (Gp_role == GP_ROLE_DISPATCH)
return;
snapshot = RegisterSnapshot(GetLatestSnapshot());
fileSegTotals = GetAOCSSSegFilesTotals(rel, snapshot);
*tuples = (double)fileSegTotals->totaltuples;
/* Quick exit if empty */
if (*tuples == 0)
{
UnregisterSnapshot(snapshot);
*pages = 0;
return;
}
Assert(fileSegTotals->totalbytesuncompressed > 0);
*pages = RelationGuessNumberOfBlocksFromSize(
(uint64)fileSegTotals->totalbytesuncompressed);
UnregisterSnapshot(snapshot);
/*
* Do not bother scanning the visimap aux table.
* Investigate if really needed.
*
* Refer to the comments at the end of function
* appendonly_estimate_rel_size().
*/
return;
}
/* ------------------------------------------------------------------------
* Executor related callbacks for the heap AM
* ------------------------------------------------------------------------
*/
static bool
aoco_scan_bitmap_next_block(TableScanDesc scan,
TBMIterateResult *tbmres)
{
AOCSBitmapScan aocsBitmapScan = (AOCSBitmapScan)scan;
/* Make sure we never cross 15-bit offset number [MPP-24326] */
Assert(tbmres->ntuples <= INT16_MAX + 1);
/*
* Start scanning from the beginning of the offsets array (or
* at first "offset number" if it's a lossy page).
* In nodeBitmapHeapscan.c's BitmapHeapNext. After call
* `table_scan_bitmap_next_block` and return false, it doesn't
* clean the tbmres. Then it'll call aoco_scan_bitmap_next_tuple
* to try to get tuples from the skipped page, and it'll return false.
* Althouth aoco_scan_bitmap_next_tuple works fine.
* But it still be better to set these init value before return in case
* of wrong init value.
*/
aocsBitmapScan->rs_cindex = 0;
/* If tbmres contains no tuples, continue. */
if (tbmres->ntuples == 0)
return false;
/*
* which descriptor to be used for fetching the data
*/
aocsBitmapScan->whichDesc = (tbmres->recheck) ? RECHECK : NO_RECHECK;
return true;
}
static bool
aoco_scan_bitmap_next_tuple(TableScanDesc scan,
TBMIterateResult *tbmres,
TupleTableSlot *slot)
{
AOCSBitmapScan aocsBitmapScan = (AOCSBitmapScan)scan;
AOCSFetchDesc aocoFetchDesc;
OffsetNumber pseudoOffset;
ItemPointerData pseudoTid;
AOTupleId aoTid;
int numTuples;
aocoFetchDesc = aocsBitmapScan->bitmapScanDesc[aocsBitmapScan->whichDesc].bitmapFetch;
if (aocoFetchDesc == NULL)
{
aocoFetchDesc = aocs_fetch_init(aocsBitmapScan->rs_base.rs_rd,
aocsBitmapScan->rs_base.rs_snapshot,
aocsBitmapScan->appendOnlyMetaDataSnapshot,
aocsBitmapScan->bitmapScanDesc[aocsBitmapScan->whichDesc].proj);
aocsBitmapScan->bitmapScanDesc[aocsBitmapScan->whichDesc].bitmapFetch = aocoFetchDesc;
}
ExecClearTuple(slot);
/* ntuples == -1 indicates a lossy page */
numTuples = (tbmres->ntuples == -1) ? INT16_MAX + 1 : tbmres->ntuples;
while (aocsBitmapScan->rs_cindex < numTuples)
{
/*
* If it's a lossy page, iterate through all possible "offset numbers".
* Otherwise iterate through the array of "offset numbers".
*/
if (tbmres->ntuples == -1)
{
/*
* +1 to convert index to offset, since TID offsets are not zero
* based.
*/
pseudoOffset = aocsBitmapScan->rs_cindex + 1;
}
else
pseudoOffset = tbmres->offsets[aocsBitmapScan->rs_cindex];
aocsBitmapScan->rs_cindex++;
/*
* Okay to fetch the tuple
*/
ItemPointerSet(&pseudoTid, tbmres->blockno, pseudoOffset);
tbm_convert_appendonly_tid_out(&pseudoTid, &aoTid);
if (aocs_fetch(aocoFetchDesc, &aoTid, slot))
{
/* OK to return this tuple */
ExecStoreVirtualTuple(slot);
pgstat_count_heap_fetch(aocsBitmapScan->rs_base.rs_rd);
return true;
}
}
/* Done with this block */
return false;
}
static bool
aoco_scan_sample_next_block(TableScanDesc scan, SampleScanState *scanstate)
{
/*
* GPDB_95_MERGE_FIXME: Add support for AO_COLUMN tables
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("invalid relation type"),
errhint("Sampling is only supported in heap tables.")));
}
static bool
aoco_scan_sample_next_tuple(TableScanDesc scan, SampleScanState *scanstate,
TupleTableSlot *slot)
{
/*
* GPDB_95_MERGE_FIXME: Add support for AO_COLUMN tables
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("invalid relation type"),
errhint("Sampling is only supported in heap tables.")));
}
/* ------------------------------------------------------------------------
* Definition of the AO_COLUMN table access method.
*
* NOTE: While there is a lot of functionality shared with the appendoptimized
* access method, is best for the hanlder methods to remain static in order to
* honour the contract of the access method interface.
* ------------------------------------------------------------------------
*/
static const TableAmRoutine ao_column_methods = {
.type = T_TableAmRoutine,
.slot_callbacks = aoco_slot_callbacks,
/*
* GPDB: it is needed to extract the column information for
* scans before calling beginscan. This can not happen in beginscan because
* the needed information is not available at that time. It is the caller's
* responsibility to choose to call aoco_beginscan_extractcolumns or
* aoco_beginscan.
*/
.scan_begin_extractcolumns = aoco_beginscan_extractcolumns,
/*
* GPDB: Like above but for bitmap scans.
*/
.scan_begin_extractcolumns_bm = aoco_beginscan_extractcolumns_bm,
.scan_begin = aoco_beginscan,
.scan_end = aoco_endscan,
.scan_rescan = aoco_rescan,
.scan_getnextslot = aoco_getnextslot,
.parallelscan_estimate = aoco_parallelscan_estimate,
.parallelscan_initialize = aoco_parallelscan_initialize,
.parallelscan_reinitialize = aoco_parallelscan_reinitialize,
.index_fetch_begin = aoco_index_fetch_begin,
.index_fetch_reset = aoco_index_fetch_reset,
.index_fetch_end = aoco_index_fetch_end,
.index_fetch_tuple = aoco_index_fetch_tuple,
.tuple_insert = aoco_tuple_insert,
.tuple_insert_speculative = aoco_tuple_insert_speculative,
.tuple_complete_speculative = aoco_tuple_complete_speculative,
.multi_insert = aoco_multi_insert,
.tuple_delete = aoco_tuple_delete,
.tuple_update = aoco_tuple_update,
.tuple_lock = aoco_tuple_lock,
.finish_bulk_insert = aoco_finish_bulk_insert,
.tuple_fetch_row_version = aoco_fetch_row_version,
.tuple_get_latest_tid = aoco_get_latest_tid,
.tuple_tid_valid = aoco_tuple_tid_valid,
.tuple_satisfies_snapshot = aoco_tuple_satisfies_snapshot,
.compute_xid_horizon_for_tuples = aoco_compute_xid_horizon_for_tuples,
.relation_set_new_filenode = aoco_relation_set_new_filenode,
.relation_nontransactional_truncate = aoco_relation_nontransactional_truncate,
.relation_copy_data = aoco_relation_copy_data,
.relation_copy_for_cluster = aoco_relation_copy_for_cluster,
.relation_vacuum = aoco_vacuum_rel,
.scan_analyze_next_block = aoco_scan_analyze_next_block,
.scan_analyze_next_tuple = aoco_scan_analyze_next_tuple,
.index_build_range_scan = aoco_index_build_range_scan,
.index_validate_scan = aoco_index_validate_scan,
.relation_size = aoco_relation_size,
.relation_needs_toast_table = aoco_relation_needs_toast_table,
.relation_estimate_size = aoco_estimate_rel_size,
.scan_bitmap_next_block = aoco_scan_bitmap_next_block,
.scan_bitmap_next_tuple = aoco_scan_bitmap_next_tuple,
.scan_sample_next_block = aoco_scan_sample_next_block,
.scan_sample_next_tuple = aoco_scan_sample_next_tuple
};
Datum
ao_column_tableam_handler(PG_FUNCTION_ARGS)
{
PG_RETURN_POINTER(&ao_column_methods);
}
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