void
initSpGistState(SpGistState *state, Relation index)
{
RegProcedure propOid;
Assert(index->rd_att->natts == 1);
propOid = index_getprocid(index, 1, SPGIST_PROP_PROC);
state->prop = *(SpGistOpClassProp*)DatumGetPointer(OidFunctionCall0Coll(propOid, InvalidOid));
fillTypeDesc(&state->attType, state->prop.leafType);
fillTypeDesc(&state->attNodeType, state->prop.nodeType);
fillTypeDesc(&state->attPrefixType, state->prop.prefixType);
fmgr_info_copy(&(state->chooseFn),
index_getprocinfo(index, 1, SPGIST_CHOOSE_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->picksplitFn),
index_getprocinfo(index, 1, SPGIST_PICKSPLIT_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->leafConsistentFn),
index_getprocinfo(index, 1, SPGIST_LEAFCONS_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->innerConsistentFn),
index_getprocinfo(index, 1, SPGIST_INNERCONS_PROC),
CurrentMemoryContext);
state->nodeTupDesc = CreateTemplateTupleDesc(1, false);
TupleDescInitEntry(state->nodeTupDesc, (AttrNumber) 1, NULL,
state->attNodeType.type, -1, 0);
}
static void
initRtstate(RTSTATE *rtstate, Relation index)
{
fmgr_info_copy(&rtstate->unionFn,
index_getprocinfo(index, 1, RT_UNION_PROC),
CurrentMemoryContext);
fmgr_info_copy(&rtstate->sizeFn,
index_getprocinfo(index, 1, RT_SIZE_PROC),
CurrentMemoryContext);
fmgr_info_copy(&rtstate->interFn,
index_getprocinfo(index, 1, RT_INTER_PROC),
CurrentMemoryContext);
}
void
initGinState(GinState *state, Relation index)
{
int i;
state->origTupdesc = index->rd_att;
state->oneCol = (index->rd_att->natts == 1) ? true : false;
for (i = 0; i < index->rd_att->natts; i++)
{
state->tupdesc[i] = CreateTemplateTupleDesc(2, false);
TupleDescInitEntry(state->tupdesc[i], (AttrNumber) 1, NULL,
INT2OID, -1, 0);
TupleDescInitEntry(state->tupdesc[i], (AttrNumber) 2, NULL,
index->rd_att->attrs[i]->atttypid,
index->rd_att->attrs[i]->atttypmod,
index->rd_att->attrs[i]->attndims
);
fmgr_info_copy(&(state->compareFn[i]),
index_getprocinfo(index, i + 1, GIN_COMPARE_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->extractValueFn[i]),
index_getprocinfo(index, i + 1, GIN_EXTRACTVALUE_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->extractQueryFn[i]),
index_getprocinfo(index, i + 1, GIN_EXTRACTQUERY_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->consistentFn[i]),
index_getprocinfo(index, i + 1, GIN_CONSISTENT_PROC),
CurrentMemoryContext);
/*
* Check opclass capability to do partial match.
*/
if (index_getprocid(index, i + 1, GIN_COMPARE_PARTIAL_PROC) != InvalidOid)
{
fmgr_info_copy(&(state->comparePartialFn[i]),
index_getprocinfo(index, i + 1, GIN_COMPARE_PARTIAL_PROC),
CurrentMemoryContext);
state->canPartialMatch[i] = true;
}
else
{
state->canPartialMatch[i] = false;
}
}
}
/*
* Given two deformed tuples, adjust the first one so that it's consistent
* with the summary values in both.
*/
static void
union_tuples(BrinDesc *bdesc, BrinMemTuple *a, BrinTuple *b)
{
int keyno;
BrinMemTuple *db;
MemoryContext cxt;
MemoryContext oldcxt;
/* Use our own memory context to avoid retail pfree */
cxt = AllocSetContextCreate(CurrentMemoryContext,
"brin union",
ALLOCSET_DEFAULT_SIZES);
oldcxt = MemoryContextSwitchTo(cxt);
db = brin_deform_tuple(bdesc, b);
MemoryContextSwitchTo(oldcxt);
for (keyno = 0; keyno < bdesc->bd_tupdesc->natts; keyno++)
{
FmgrInfo *unionFn;
BrinValues *col_a = &a->bt_columns[keyno];
BrinValues *col_b = &db->bt_columns[keyno];
unionFn = index_getprocinfo(bdesc->bd_index, keyno + 1,
BRIN_PROCNUM_UNION);
FunctionCall3Coll(unionFn,
bdesc->bd_index->rd_indcollation[keyno],
PointerGetDatum(bdesc),
PointerGetDatum(col_a),
PointerGetDatum(col_b));
}
MemoryContextDelete(cxt);
}
/*
* _bt_mkscankey_nodata
* Build an insertion scan key that contains 3-way comparator routines
* appropriate to the key datatypes, but no comparison data. The
* comparison data ultimately used must match the key datatypes.
*
* The result cannot be used with _bt_compare(), unless comparison
* data is first stored into the key entries. Currently this
* routine is only called by nbtsort.c and tuplesort.c, which have
* their own comparison routines.
*/
ScanKey
_bt_mkscankey_nodata(Relation rel)
{
ScanKey skey;
int natts;
int16 *indoption;
int i;
natts = RelationGetNumberOfAttributes(rel);
indoption = rel->rd_indoption;
skey = (ScanKey) palloc(natts * sizeof(ScanKeyData));
for (i = 0; i < natts; i++)
{
FmgrInfo *procinfo;
int flags;
/*
* We can use the cached (default) support procs since no cross-type
* comparison can be needed.
*/
procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC);
flags = SK_ISNULL | (indoption[i] << SK_BT_INDOPTION_SHIFT);
ScanKeyEntryInitializeWithInfo(&skey[i],
flags,
(AttrNumber) (i + 1),
InvalidStrategy,
InvalidOid,
procinfo,
(Datum) 0);
}
return skey;
}
/*
* bt_mk_scankey_nodata
* Build an insertion scan key that contains 3-way comparator routines
* appropriate to the key datatypes, but no comparison data. The
* comparison data ultimately used must match the key datatypes.
*
* The result cannot be used with bt_compare(), unless comparison
* data is first stored into the key entries. Currently this
* routine is only called by nbtsort.c and tuplesort.c, which have
* their own comparison routines.
*/
struct scankey *bt_mk_scankey_nodata(struct relation *rel)
{
struct scankey *skey;
int natts;
int16 *indoption;
int i;
natts = REL_GET_NR_ATTR(rel);
indoption = rel->rd_indoption;
skey = (struct scankey *)palloc(natts * sizeof(struct scankey));
for (i = 0; i < natts; i++) {
struct fmgr_info *procinfo;
int flags;
/*
* We can use the cached (default) support procs since no cross-type
* comparison can be needed.
*/
procinfo = index_getprocinfo(rel, i + 1, BT_ORDER_PROC);
flags = SK_ISNULL | (indoption[i] << SK_BT_INDEX_OPT_SHIFT);
scankey_init_info(&skey[i],
flags,
(attr_nr_t)(i + 1),
INVALID_STRAT,
INVALID_OID,
rel->rd_indcollation[i],
procinfo,
(datum_t) 0);
}
return skey;
}
/*
* Per-heap-tuple callback for IndexBuildHeapScan.
*
* Note we don't worry about the page range at the end of the table here; it is
* present in the build state struct after we're called the last time, but not
* inserted into the index. Caller must ensure to do so, if appropriate.
*/
static void
brinbuildCallback(Relation index,
HeapTuple htup,
Datum *values,
bool *isnull,
bool tupleIsAlive,
void *brstate)
{
BrinBuildState *state = (BrinBuildState *) brstate;
BlockNumber thisblock;
int i;
thisblock = ItemPointerGetBlockNumber(&htup->t_self);
/*
* If we're in a block that belongs to a future range, summarize what
* we've got and start afresh. Note the scan might have skipped many
* pages, if they were devoid of live tuples; make sure to insert index
* tuples for those too.
*/
while (thisblock > state->bs_currRangeStart + state->bs_pagesPerRange - 1)
{
BRIN_elog((DEBUG2,
"brinbuildCallback: completed a range: %u--%u",
state->bs_currRangeStart,
state->bs_currRangeStart + state->bs_pagesPerRange));
/* create the index tuple and insert it */
form_and_insert_tuple(state);
/* set state to correspond to the next range */
state->bs_currRangeStart += state->bs_pagesPerRange;
/* re-initialize state for it */
brin_memtuple_initialize(state->bs_dtuple, state->bs_bdesc);
}
/* Accumulate the current tuple into the running state */
for (i = 0; i < state->bs_bdesc->bd_tupdesc->natts; i++)
{
FmgrInfo *addValue;
BrinValues *col;
Form_pg_attribute attr = TupleDescAttr(state->bs_bdesc->bd_tupdesc, i);
col = &state->bs_dtuple->bt_columns[i];
addValue = index_getprocinfo(index, i + 1,
BRIN_PROCNUM_ADDVALUE);
/*
* Update dtuple state, if and as necessary.
*/
FunctionCall4Coll(addValue,
attr->attcollation,
PointerGetDatum(state->bs_bdesc),
PointerGetDatum(col),
values[i], isnull[i]);
}
}
/*
* Build a BrinDesc used to create or scan a BRIN index
*/
BrinDesc *
brin_build_desc(Relation rel)
{
BrinOpcInfo **opcinfo;
BrinDesc *bdesc;
TupleDesc tupdesc;
int totalstored = 0;
int keyno;
long totalsize;
MemoryContext cxt;
MemoryContext oldcxt;
cxt = AllocSetContextCreate(CurrentMemoryContext,
"brin desc cxt",
ALLOCSET_SMALL_INITSIZE,
ALLOCSET_SMALL_MINSIZE,
ALLOCSET_SMALL_MAXSIZE);
oldcxt = MemoryContextSwitchTo(cxt);
tupdesc = RelationGetDescr(rel);
/*
* Obtain BrinOpcInfo for each indexed column. While at it, accumulate
* the number of columns stored, since the number is opclass-defined.
*/
opcinfo = (BrinOpcInfo **) palloc(sizeof(BrinOpcInfo *) * tupdesc->natts);
for (keyno = 0; keyno < tupdesc->natts; keyno++)
{
FmgrInfo *opcInfoFn;
opcInfoFn = index_getprocinfo(rel, keyno + 1, BRIN_PROCNUM_OPCINFO);
opcinfo[keyno] = (BrinOpcInfo *)
DatumGetPointer(FunctionCall1(opcInfoFn,
tupdesc->attrs[keyno]->atttypid));
totalstored += opcinfo[keyno]->oi_nstored;
}
/* Allocate our result struct and fill it in */
totalsize = offsetof(BrinDesc, bd_info) +
sizeof(BrinOpcInfo *) * tupdesc->natts;
bdesc = palloc(totalsize);
bdesc->bd_context = cxt;
bdesc->bd_index = rel;
bdesc->bd_tupdesc = tupdesc;
bdesc->bd_disktdesc = NULL; /* generated lazily */
bdesc->bd_totalstored = totalstored;
for (keyno = 0; keyno < tupdesc->natts; keyno++)
bdesc->bd_info[keyno] = opcinfo[keyno];
pfree(opcinfo);
MemoryContextSwitchTo(oldcxt);
return bdesc;
}
/*
* _hash_datum2hashkey -- given a Datum, call the index's hash procedure
*
* The Datum is assumed to be of the index's column type, so we can use the
* "primary" hash procedure that's tracked for us by the generic index code.
*/
uint32
_hash_datum2hashkey(Relation rel, Datum key)
{
FmgrInfo *procinfo;
/* XXX assumes index has only one attribute */
procinfo = index_getprocinfo(rel, 1, HASHPROC);
return DatumGetUInt32(FunctionCall1(procinfo, key));
}
/*
* _hash_datum2hashkey -- given a Datum, call the index's hash procedure
*
* The Datum is assumed to be of the index's column type, so we can use the
* "primary" hash procedure that's tracked for us by the generic index code.
*/
uint32
_hash_datum2hashkey(Relation rel, Datum key)
{
FmgrInfo *procinfo;
Oid collation;
/* XXX assumes index has only one attribute */
procinfo = index_getprocinfo(rel, 1, HASHPROC);
collation = rel->rd_indcollation[0];
return DatumGetUInt32(FunctionCall1Coll(procinfo, collation, key));
}
/*
* Fill BloomState structure for particular index.
*/
void
initBloomState(BloomState *state, Relation index)
{
int i;
state->nColumns = index->rd_att->natts;
/* Initialize hash function for each attribute */
for (i = 0; i < index->rd_att->natts; i++)
{
fmgr_info_copy(&(state->hashFn[i]),
index_getprocinfo(index, i + 1, BLOOM_HASH_PROC),
CurrentMemoryContext);
state->collations[i] = index->rd_indcollation[i];
}
/* Initialize amcache if needed with options from metapage */
if (!index->rd_amcache)
{
Buffer buffer;
Page page;
BloomMetaPageData *meta;
BloomOptions *opts;
opts = MemoryContextAlloc(index->rd_indexcxt, sizeof(BloomOptions));
buffer = ReadBuffer(index, BLOOM_METAPAGE_BLKNO);
LockBuffer(buffer, BUFFER_LOCK_SHARE);
page = BufferGetPage(buffer);
if (!BloomPageIsMeta(page))
elog(ERROR, "Relation is not a bloom index");
meta = BloomPageGetMeta(BufferGetPage(buffer));
if (meta->magickNumber != BLOOM_MAGICK_NUMBER)
elog(ERROR, "Relation is not a bloom index");
*opts = meta->opts;
UnlockReleaseBuffer(buffer);
index->rd_amcache = (void *) opts;
}
memcpy(&state->opts, index->rd_amcache, sizeof(state->opts));
state->sizeOfBloomTuple = BLOOMTUPLEHDRSZ +
sizeof(BloomSignatureWord) * state->opts.bloomLength;
}
void
initBloomState(BloomState *state, Relation index)
{
int i;
state->nColumns = index->rd_att->natts;
for (i = 0; i < index->rd_att->natts; i++)
{
fmgr_info_copy(&(state->hashFn[i]),
index_getprocinfo(index, i + 1, BLOOM_HASH_PROC),
CurrentMemoryContext);
}
if (!index->rd_amcache)
{
Buffer buffer;
BloomMetaPageData *meta;
BloomOptions *opts;
opts = MemoryContextAlloc(index->rd_indexcxt, sizeof(BloomOptions));
buffer = ReadBuffer(index, BLOOM_METAPAGE_BLKNO);
LockBuffer(buffer, BUFFER_LOCK_SHARE);
if (!BloomPageIsMeta(BufferGetPage(buffer)))
elog(ERROR,"Relation is not a bloom index");
meta = BloomPageGetMeta(BufferGetPage(buffer));
if (meta->magickNumber != BLOOM_MAGICK_NUMBER)
elog(ERROR,"Relation is not a bloom index");
*opts = meta->opts;
UnlockReleaseBuffer(buffer);
index->rd_amcache = (void*)opts;
}
state->opts = (BloomOptions*)index->rd_amcache;
state->sizeOfBloomTuple = BLOOMTUPLEHDRSZ + sizeof(SignType) * state->opts->bloomLength;
}
void
initGISTstate(GISTSTATE *giststate, Relation index)
{
int i;
if (index->rd_att->natts > INDEX_MAX_KEYS)
elog(ERROR, "numberOfAttributes %d > %d",
index->rd_att->natts, INDEX_MAX_KEYS);
giststate->tupdesc = index->rd_att;
for (i = 0; i < index->rd_att->natts; i++)
{
fmgr_info_copy(&(giststate->consistentFn[i]),
index_getprocinfo(index, i + 1, GIST_CONSISTENT_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->unionFn[i]),
index_getprocinfo(index, i + 1, GIST_UNION_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->compressFn[i]),
index_getprocinfo(index, i + 1, GIST_COMPRESS_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->decompressFn[i]),
index_getprocinfo(index, i + 1, GIST_DECOMPRESS_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->penaltyFn[i]),
index_getprocinfo(index, i + 1, GIST_PENALTY_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->picksplitFn[i]),
index_getprocinfo(index, i + 1, GIST_PICKSPLIT_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->equalFn[i]),
index_getprocinfo(index, i + 1, GIST_EQUAL_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->distanceFn[i]),
index_getprocinfo(index, i + 1, GIST_DISTANCE_PROC),
CurrentMemoryContext);
}
}
/*
* _bt_mkscankey
* Build an insertion scan key that contains comparison data from itup
* as well as comparator routines appropriate to the key datatypes.
*
* The result is intended for use with _bt_compare().
*/
ScanKey
_bt_mkscankey(Relation rel, IndexTuple itup)
{
ScanKey skey;
TupleDesc itupdesc;
int natts;
int16 *indoption;
int i;
itupdesc = RelationGetDescr(rel);
natts = RelationGetNumberOfAttributes(rel);
indoption = rel->rd_indoption;
skey = (ScanKey) palloc(natts * sizeof(ScanKeyData));
for (i = 0; i < natts; i++)
{
FmgrInfo *procinfo;
Datum arg;
bool null;
int flags;
/*
* We can use the cached (default) support procs since no cross-type
* comparison can be needed.
*/
procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC);
arg = index_getattr(itup, i + 1, itupdesc, &null);
flags = (null ? SK_ISNULL : 0) | (indoption[i] << SK_BT_INDOPTION_SHIFT);
ScanKeyEntryInitializeWithInfo(&skey[i],
flags,
(AttrNumber) (i + 1),
InvalidStrategy,
InvalidOid,
rel->rd_indcollation[i],
procinfo,
arg);
}
return skey;
}
/*
* bt_mk_scankey
* Build an insertion scan key that contains comparison data from itup
* as well as comparator routines appropriate to the key datatypes.
*
* The result is intended for use with bt_compare().
*/
struct scankey *bt_mk_scankey(struct relation* rel, struct index_tuple* itup)
{
struct scankey *skey;
struct tuple *itupdesc;
int natts;
int16 *indoption;
int i;
itupdesc = REL_DESC(rel);
natts = REL_GET_NR_ATTR(rel);
indoption = rel->rd_indoption;
skey = (struct scankey *)palloc(natts * sizeof(struct scankey));
for (i = 0; i < natts; i++) {
struct fmgr_info *procinfo;
datum_t arg;
bool null;
int flags;
/*
* We can use the cached (default) support procs since no cross-type
* comparison can be needed.
*/
procinfo = index_getprocinfo(rel, i + 1, BT_ORDER_PROC);
arg = index_getattr(itup, i + 1, itupdesc, &null);
flags = (null ? SK_ISNULL : 0) | (indoption[i] << SK_BT_INDEX_OPT_SHIFT);
scankey_init_info(&skey[i],
flags,
(attr_nr_t)(i + 1),
INVALID_STRAT,
INVALID_OID,
rel->rd_indcollation[i],
procinfo,
arg);
}
return skey;
}
/*
* initGinState: fill in an empty GinState struct to describe the index
*
* Note: assorted subsidiary data is allocated in the CurrentMemoryContext.
*/
void
initGinState(GinState *state, Relation index)
{
TupleDesc origTupdesc = RelationGetDescr(index);
int i;
MemSet(state, 0, sizeof(GinState));
state->index = index;
state->oneCol = (origTupdesc->natts == 1) ? true : false;
state->origTupdesc = origTupdesc;
for (i = 0; i < origTupdesc->natts; i++)
{
if (state->oneCol)
state->tupdesc[i] = state->origTupdesc;
else
{
state->tupdesc[i] = CreateTemplateTupleDesc(2, false);
TupleDescInitEntry(state->tupdesc[i], (AttrNumber) 1, NULL,
INT2OID, -1, 0);
TupleDescInitEntry(state->tupdesc[i], (AttrNumber) 2, NULL,
origTupdesc->attrs[i]->atttypid,
origTupdesc->attrs[i]->atttypmod,
origTupdesc->attrs[i]->attndims);
TupleDescInitEntryCollation(state->tupdesc[i], (AttrNumber) 2,
origTupdesc->attrs[i]->attcollation);
}
/*
* If the compare proc isn't specified in the opclass definition, look
* up the index key type's default btree comparator.
*/
if (index_getprocid(index, i + 1, GIN_COMPARE_PROC) != InvalidOid)
{
fmgr_info_copy(&(state->compareFn[i]),
index_getprocinfo(index, i + 1, GIN_COMPARE_PROC),
CurrentMemoryContext);
}
else
{
TypeCacheEntry *typentry;
typentry = lookup_type_cache(origTupdesc->attrs[i]->atttypid,
TYPECACHE_CMP_PROC_FINFO);
if (!OidIsValid(typentry->cmp_proc_finfo.fn_oid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_FUNCTION),
errmsg("could not identify a comparison function for type %s",
format_type_be(origTupdesc->attrs[i]->atttypid))));
fmgr_info_copy(&(state->compareFn[i]),
&(typentry->cmp_proc_finfo),
CurrentMemoryContext);
}
/* Opclass must always provide extract procs */
fmgr_info_copy(&(state->extractValueFn[i]),
index_getprocinfo(index, i + 1, GIN_EXTRACTVALUE_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->extractQueryFn[i]),
index_getprocinfo(index, i + 1, GIN_EXTRACTQUERY_PROC),
CurrentMemoryContext);
/*
* Check opclass capability to do tri-state or binary logic consistent
* check.
*/
if (index_getprocid(index, i + 1, GIN_TRICONSISTENT_PROC) != InvalidOid)
{
fmgr_info_copy(&(state->triConsistentFn[i]),
index_getprocinfo(index, i + 1, GIN_TRICONSISTENT_PROC),
CurrentMemoryContext);
}
if (index_getprocid(index, i + 1, GIN_CONSISTENT_PROC) != InvalidOid)
{
fmgr_info_copy(&(state->consistentFn[i]),
index_getprocinfo(index, i + 1, GIN_CONSISTENT_PROC),
CurrentMemoryContext);
}
if (state->consistentFn[i].fn_oid == InvalidOid &&
state->triConsistentFn[i].fn_oid == InvalidOid)
{
elog(ERROR, "missing GIN support function (%d or %d) for attribute %d of index \"%s\"",
GIN_CONSISTENT_PROC, GIN_TRICONSISTENT_PROC,
i + 1, RelationGetRelationName(index));
}
/*
* Check opclass capability to do partial match.
*/
if (index_getprocid(index, i + 1, GIN_COMPARE_PARTIAL_PROC) != InvalidOid)
{
fmgr_info_copy(&(state->comparePartialFn[i]),
index_getprocinfo(index, i + 1, GIN_COMPARE_PARTIAL_PROC),
CurrentMemoryContext);
state->canPartialMatch[i] = true;
}
else
{
state->canPartialMatch[i] = false;
}
/*
* If the index column has a specified collation, we should honor that
* while doing comparisons. However, we may have a collatable storage
* type for a noncollatable indexed data type (for instance, hstore
* uses text index entries). If there's no index collation then
* specify default collation in case the support functions need
* collation. This is harmless if the support functions don't care
* about collation, so we just do it unconditionally. (We could
* alternatively call get_typcollation, but that seems like expensive
* overkill --- there aren't going to be any cases where a GIN storage
* type has a nondefault collation.)
*/
if (OidIsValid(index->rd_indcollation[i]))
state->supportCollation[i] = index->rd_indcollation[i];
else
state->supportCollation[i] = DEFAULT_COLLATION_OID;
}
}
/*
* initGinState: fill in an empty GinState struct to describe the index
*
* Note: assorted subsidiary data is allocated in the CurrentMemoryContext.
*/
void
initGinState(GinState *state, Relation index)
{
TupleDesc origTupdesc = RelationGetDescr(index);
int i;
MemSet(state, 0, sizeof(GinState));
state->index = index;
state->oneCol = (origTupdesc->natts == 1) ? true : false;
state->origTupdesc = origTupdesc;
for (i = 0; i < origTupdesc->natts; i++)
{
if (state->oneCol)
state->tupdesc[i] = state->origTupdesc;
else
{
state->tupdesc[i] = CreateTemplateTupleDesc(2, false);
TupleDescInitEntry(state->tupdesc[i], (AttrNumber) 1, NULL,
INT2OID, -1, 0);
TupleDescInitEntry(state->tupdesc[i], (AttrNumber) 2, NULL,
origTupdesc->attrs[i]->atttypid,
origTupdesc->attrs[i]->atttypmod,
origTupdesc->attrs[i]->attndims);
TupleDescInitEntryCollation(state->tupdesc[i], (AttrNumber) 2,
origTupdesc->attrs[i]->attcollation);
}
fmgr_info_copy(&(state->compareFn[i]),
index_getprocinfo(index, i + 1, GIN_COMPARE_PROC),
CurrentMemoryContext);
/*
* If the index column has a specified collation, index_getprocinfo
* will have installed it into the fmgr info, and we should honor it.
* However, we may have a collatable storage type for a noncollatable
* indexed data type (for instance, hstore uses text index entries).
* If there's no index collation then specify default collation in
* case the comparison function needs one. This is harmless if the
* comparison function doesn't care about collation, so we just do it
* unconditionally. (We could alternatively call get_typcollation,
* but that seems like expensive overkill --- there aren't going to be
* any cases where a GIN storage type has a nondefault collation.)
*/
if (!OidIsValid(state->compareFn[i].fn_collation))
fmgr_info_set_collation(DEFAULT_COLLATION_OID,
&(state->compareFn[i]));
fmgr_info_copy(&(state->extractValueFn[i]),
index_getprocinfo(index, i + 1, GIN_EXTRACTVALUE_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->extractQueryFn[i]),
index_getprocinfo(index, i + 1, GIN_EXTRACTQUERY_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(state->consistentFn[i]),
index_getprocinfo(index, i + 1, GIN_CONSISTENT_PROC),
CurrentMemoryContext);
/*
* Check opclass capability to do partial match.
*/
if (index_getprocid(index, i + 1, GIN_COMPARE_PARTIAL_PROC) != InvalidOid)
{
fmgr_info_copy(&(state->comparePartialFn[i]),
index_getprocinfo(index, i + 1, GIN_COMPARE_PARTIAL_PROC),
CurrentMemoryContext);
/* As above, install collation spec in case compare fn needs it */
if (!OidIsValid(state->comparePartialFn[i].fn_collation))
fmgr_info_set_collation(DEFAULT_COLLATION_OID,
&(state->comparePartialFn[i]));
state->canPartialMatch[i] = true;
}
else
{
state->canPartialMatch[i] = false;
}
}
}
/*
* Execute the index scan.
*
* This works by reading index TIDs from the revmap, and obtaining the index
* tuples pointed to by them; the summary values in the index tuples are
* compared to the scan keys. We return into the TID bitmap all the pages in
* ranges corresponding to index tuples that match the scan keys.
*
* If a TID from the revmap is read as InvalidTID, we know that range is
* unsummarized. Pages in those ranges need to be returned regardless of scan
* keys.
*/
int64
bringetbitmap(IndexScanDesc scan, TIDBitmap *tbm)
{
Relation idxRel = scan->indexRelation;
Buffer buf = InvalidBuffer;
BrinDesc *bdesc;
Oid heapOid;
Relation heapRel;
BrinOpaque *opaque;
BlockNumber nblocks;
BlockNumber heapBlk;
int totalpages = 0;
FmgrInfo *consistentFn;
MemoryContext oldcxt;
MemoryContext perRangeCxt;
opaque = (BrinOpaque *) scan->opaque;
bdesc = opaque->bo_bdesc;
pgstat_count_index_scan(idxRel);
/*
* We need to know the size of the table so that we know how long to
* iterate on the revmap.
*/
heapOid = IndexGetRelation(RelationGetRelid(idxRel), false);
heapRel = heap_open(heapOid, AccessShareLock);
nblocks = RelationGetNumberOfBlocks(heapRel);
heap_close(heapRel, AccessShareLock);
/*
* Make room for the consistent support procedures of indexed columns. We
* don't look them up here; we do that lazily the first time we see a scan
* key reference each of them. We rely on zeroing fn_oid to InvalidOid.
*/
consistentFn = palloc0(sizeof(FmgrInfo) * bdesc->bd_tupdesc->natts);
/*
* Setup and use a per-range memory context, which is reset every time we
* loop below. This avoids having to free the tuples within the loop.
*/
perRangeCxt = AllocSetContextCreate(CurrentMemoryContext,
"bringetbitmap cxt",
ALLOCSET_DEFAULT_SIZES);
oldcxt = MemoryContextSwitchTo(perRangeCxt);
/*
* Now scan the revmap. We start by querying for heap page 0,
* incrementing by the number of pages per range; this gives us a full
* view of the table.
*/
for (heapBlk = 0; heapBlk < nblocks; heapBlk += opaque->bo_pagesPerRange)
{
bool addrange;
BrinTuple *tup;
OffsetNumber off;
Size size;
CHECK_FOR_INTERRUPTS();
MemoryContextResetAndDeleteChildren(perRangeCxt);
tup = brinGetTupleForHeapBlock(opaque->bo_rmAccess, heapBlk, &buf,
&off, &size, BUFFER_LOCK_SHARE,
scan->xs_snapshot);
if (tup)
{
tup = brin_copy_tuple(tup, size);
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
}
/*
* For page ranges with no indexed tuple, we must return the whole
* range; otherwise, compare it to the scan keys.
*/
if (tup == NULL)
{
addrange = true;
}
else
{
BrinMemTuple *dtup;
dtup = brin_deform_tuple(bdesc, tup);
if (dtup->bt_placeholder)
{
/*
* Placeholder tuples are always returned, regardless of the
* values stored in them.
*/
addrange = true;
}
else
{
int keyno;
/*
* Compare scan keys with summary values stored for the range.
* If scan keys are matched, the page range must be added to
* the bitmap. We initially assume the range needs to be
* added; in particular this serves the case where there are
* no keys.
*/
addrange = true;
for (keyno = 0; keyno < scan->numberOfKeys; keyno++)
{
ScanKey key = &scan->keyData[keyno];
AttrNumber keyattno = key->sk_attno;
BrinValues *bval = &dtup->bt_columns[keyattno - 1];
Datum add;
/*
* The collation of the scan key must match the collation
* used in the index column (but only if the search is not
* IS NULL/ IS NOT NULL). Otherwise we shouldn't be using
* this index ...
*/
Assert((key->sk_flags & SK_ISNULL) ||
(key->sk_collation ==
bdesc->bd_tupdesc->attrs[keyattno - 1]->attcollation));
/* First time this column? look up consistent function */
if (consistentFn[keyattno - 1].fn_oid == InvalidOid)
{
FmgrInfo *tmp;
tmp = index_getprocinfo(idxRel, keyattno,
BRIN_PROCNUM_CONSISTENT);
fmgr_info_copy(&consistentFn[keyattno - 1], tmp,
CurrentMemoryContext);
}
/*
* Check whether the scan key is consistent with the page
* range values; if so, have the pages in the range added
* to the output bitmap.
*
* When there are multiple scan keys, failure to meet the
* criteria for a single one of them is enough to discard
* the range as a whole, so break out of the loop as soon
* as a false return value is obtained.
*/
add = FunctionCall3Coll(&consistentFn[keyattno - 1],
key->sk_collation,
PointerGetDatum(bdesc),
PointerGetDatum(bval),
PointerGetDatum(key));
addrange = DatumGetBool(add);
if (!addrange)
break;
}
}
}
/* add the pages in the range to the output bitmap, if needed */
if (addrange)
{
BlockNumber pageno;
for (pageno = heapBlk;
pageno <= heapBlk + opaque->bo_pagesPerRange - 1;
pageno++)
{
MemoryContextSwitchTo(oldcxt);
tbm_add_page(tbm, pageno);
totalpages++;
MemoryContextSwitchTo(perRangeCxt);
}
}
}
MemoryContextSwitchTo(oldcxt);
MemoryContextDelete(perRangeCxt);
if (buf != InvalidBuffer)
ReleaseBuffer(buf);
/*
* XXX We have an approximation of the number of *pages* that our scan
* returns, but we don't have a precise idea of the number of heap tuples
* involved.
*/
return totalpages * 10;
}
/*
* A tuple in the heap is being inserted. To keep a brin index up to date,
* we need to obtain the relevant index tuple and compare its stored values
* with those of the new tuple. If the tuple values are not consistent with
* the summary tuple, we need to update the index tuple.
*
* If the range is not currently summarized (i.e. the revmap returns NULL for
* it), there's nothing to do.
*/
bool
brininsert(Relation idxRel, Datum *values, bool *nulls,
ItemPointer heaptid, Relation heapRel,
IndexUniqueCheck checkUnique)
{
BlockNumber pagesPerRange;
BrinDesc *bdesc = NULL;
BrinRevmap *revmap;
Buffer buf = InvalidBuffer;
MemoryContext tupcxt = NULL;
MemoryContext oldcxt = NULL;
revmap = brinRevmapInitialize(idxRel, &pagesPerRange, NULL);
for (;;)
{
bool need_insert = false;
OffsetNumber off;
BrinTuple *brtup;
BrinMemTuple *dtup;
BlockNumber heapBlk;
int keyno;
CHECK_FOR_INTERRUPTS();
heapBlk = ItemPointerGetBlockNumber(heaptid);
/* normalize the block number to be the first block in the range */
heapBlk = (heapBlk / pagesPerRange) * pagesPerRange;
brtup = brinGetTupleForHeapBlock(revmap, heapBlk, &buf, &off, NULL,
BUFFER_LOCK_SHARE, NULL);
/* if range is unsummarized, there's nothing to do */
if (!brtup)
break;
/* First time through? */
if (bdesc == NULL)
{
bdesc = brin_build_desc(idxRel);
tupcxt = AllocSetContextCreate(CurrentMemoryContext,
"brininsert cxt",
ALLOCSET_DEFAULT_SIZES);
oldcxt = MemoryContextSwitchTo(tupcxt);
}
dtup = brin_deform_tuple(bdesc, brtup);
/*
* Compare the key values of the new tuple to the stored index values;
* our deformed tuple will get updated if the new tuple doesn't fit
* the original range (note this means we can't break out of the loop
* early). Make a note of whether this happens, so that we know to
* insert the modified tuple later.
*/
for (keyno = 0; keyno < bdesc->bd_tupdesc->natts; keyno++)
{
Datum result;
BrinValues *bval;
FmgrInfo *addValue;
bval = &dtup->bt_columns[keyno];
addValue = index_getprocinfo(idxRel, keyno + 1,
BRIN_PROCNUM_ADDVALUE);
result = FunctionCall4Coll(addValue,
idxRel->rd_indcollation[keyno],
PointerGetDatum(bdesc),
PointerGetDatum(bval),
values[keyno],
nulls[keyno]);
/* if that returned true, we need to insert the updated tuple */
need_insert |= DatumGetBool(result);
}
if (!need_insert)
{
/*
* The tuple is consistent with the new values, so there's nothing
* to do.
*/
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
}
else
{
Page page = BufferGetPage(buf);
ItemId lp = PageGetItemId(page, off);
Size origsz;
BrinTuple *origtup;
Size newsz;
BrinTuple *newtup;
bool samepage;
/*
* Make a copy of the old tuple, so that we can compare it after
* re-acquiring the lock.
*/
origsz = ItemIdGetLength(lp);
origtup = brin_copy_tuple(brtup, origsz);
/*
* Before releasing the lock, check if we can attempt a same-page
* update. Another process could insert a tuple concurrently in
* the same page though, so downstream we must be prepared to cope
* if this turns out to not be possible after all.
*/
newtup = brin_form_tuple(bdesc, heapBlk, dtup, &newsz);
samepage = brin_can_do_samepage_update(buf, origsz, newsz);
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
/*
* Try to update the tuple. If this doesn't work for whatever
* reason, we need to restart from the top; the revmap might be
* pointing at a different tuple for this block now, so we need to
* recompute to ensure both our new heap tuple and the other
* inserter's are covered by the combined tuple. It might be that
* we don't need to update at all.
*/
if (!brin_doupdate(idxRel, pagesPerRange, revmap, heapBlk,
buf, off, origtup, origsz, newtup, newsz,
samepage))
{
/* no luck; start over */
MemoryContextResetAndDeleteChildren(tupcxt);
continue;
}
}
/* success! */
break;
}
brinRevmapTerminate(revmap);
if (BufferIsValid(buf))
ReleaseBuffer(buf);
if (bdesc != NULL)
{
brin_free_desc(bdesc);
MemoryContextSwitchTo(oldcxt);
MemoryContextDelete(tupcxt);
}
return false;
}
/*
* A tuple in the heap is being inserted. To keep a brin index up to date,
* we need to obtain the relevant index tuple and compare its stored values
* with those of the new tuple. If the tuple values are not consistent with
* the summary tuple, we need to update the index tuple.
*
* If the range is not currently summarized (i.e. the revmap returns NULL for
* it), there's nothing to do.
*/
Datum
brininsert(PG_FUNCTION_ARGS)
{
Relation idxRel = (Relation) PG_GETARG_POINTER(0);
Datum *values = (Datum *) PG_GETARG_POINTER(1);
bool *nulls = (bool *) PG_GETARG_POINTER(2);
ItemPointer heaptid = (ItemPointer) PG_GETARG_POINTER(3);
/* we ignore the rest of our arguments */
BlockNumber pagesPerRange;
BrinDesc *bdesc = NULL;
BrinRevmap *revmap;
Buffer buf = InvalidBuffer;
MemoryContext tupcxt = NULL;
MemoryContext oldcxt = NULL;
revmap = brinRevmapInitialize(idxRel, &pagesPerRange);
for (;;)
{
bool need_insert = false;
OffsetNumber off;
BrinTuple *brtup;
BrinMemTuple *dtup;
BlockNumber heapBlk;
int keyno;
#ifdef USE_ASSERT_CHECKING
BrinTuple *tmptup;
BrinMemTuple *tmpdtup;
Size tmpsiz;
#endif
CHECK_FOR_INTERRUPTS();
heapBlk = ItemPointerGetBlockNumber(heaptid);
/* normalize the block number to be the first block in the range */
heapBlk = (heapBlk / pagesPerRange) * pagesPerRange;
brtup = brinGetTupleForHeapBlock(revmap, heapBlk, &buf, &off, NULL,
BUFFER_LOCK_SHARE);
/* if range is unsummarized, there's nothing to do */
if (!brtup)
break;
/* First time through? */
if (bdesc == NULL)
{
bdesc = brin_build_desc(idxRel);
tupcxt = AllocSetContextCreate(CurrentMemoryContext,
"brininsert cxt",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
oldcxt = MemoryContextSwitchTo(tupcxt);
}
dtup = brin_deform_tuple(bdesc, brtup);
#ifdef USE_ASSERT_CHECKING
{
/*
* When assertions are enabled, we use this as an opportunity to
* test the "union" method, which would otherwise be used very
* rarely: first create a placeholder tuple, and addValue the
* value we just got into it. Then union the existing index tuple
* with the updated placeholder tuple. The tuple resulting from
* that union should be identical to the one resulting from the
* regular operation (straight addValue) below.
*
* Here we create the tuple to compare with; the actual comparison
* is below.
*/
tmptup = brin_form_placeholder_tuple(bdesc, heapBlk, &tmpsiz);
tmpdtup = brin_deform_tuple(bdesc, tmptup);
for (keyno = 0; keyno < bdesc->bd_tupdesc->natts; keyno++)
{
BrinValues *bval;
FmgrInfo *addValue;
bval = &tmpdtup->bt_columns[keyno];
addValue = index_getprocinfo(idxRel, keyno + 1,
BRIN_PROCNUM_ADDVALUE);
FunctionCall4Coll(addValue,
idxRel->rd_indcollation[keyno],
PointerGetDatum(bdesc),
PointerGetDatum(bval),
values[keyno],
nulls[keyno]);
}
union_tuples(bdesc, tmpdtup, brtup);
tmpdtup->bt_placeholder = dtup->bt_placeholder;
tmptup = brin_form_tuple(bdesc, heapBlk, tmpdtup, &tmpsiz);
}
#endif
/*
* Compare the key values of the new tuple to the stored index values;
* our deformed tuple will get updated if the new tuple doesn't fit
* the original range (note this means we can't break out of the loop
* early). Make a note of whether this happens, so that we know to
* insert the modified tuple later.
*/
for (keyno = 0; keyno < bdesc->bd_tupdesc->natts; keyno++)
{
Datum result;
BrinValues *bval;
FmgrInfo *addValue;
bval = &dtup->bt_columns[keyno];
addValue = index_getprocinfo(idxRel, keyno + 1,
BRIN_PROCNUM_ADDVALUE);
result = FunctionCall4Coll(addValue,
idxRel->rd_indcollation[keyno],
PointerGetDatum(bdesc),
PointerGetDatum(bval),
values[keyno],
nulls[keyno]);
/* if that returned true, we need to insert the updated tuple */
need_insert |= DatumGetBool(result);
}
#ifdef USE_ASSERT_CHECKING
{
/*
* Now we can compare the tuple produced by the union function
* with the one from plain addValue.
*/
BrinTuple *cmptup;
Size cmpsz;
cmptup = brin_form_tuple(bdesc, heapBlk, dtup, &cmpsz);
Assert(brin_tuples_equal(tmptup, tmpsiz, cmptup, cmpsz));
}
#endif
if (!need_insert)
{
/*
* The tuple is consistent with the new values, so there's nothing
* to do.
*/
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
}
else
{
Page page = BufferGetPage(buf);
ItemId lp = PageGetItemId(page, off);
Size origsz;
BrinTuple *origtup;
Size newsz;
BrinTuple *newtup;
bool samepage;
/*
* Make a copy of the old tuple, so that we can compare it after
* re-acquiring the lock.
*/
origsz = ItemIdGetLength(lp);
origtup = brin_copy_tuple(brtup, origsz);
/*
* Before releasing the lock, check if we can attempt a same-page
* update. Another process could insert a tuple concurrently in
* the same page though, so downstream we must be prepared to cope
* if this turns out to not be possible after all.
*/
newtup = brin_form_tuple(bdesc, heapBlk, dtup, &newsz);
samepage = brin_can_do_samepage_update(buf, origsz, newsz);
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
/*
* Try to update the tuple. If this doesn't work for whatever
* reason, we need to restart from the top; the revmap might be
* pointing at a different tuple for this block now, so we need to
* recompute to ensure both our new heap tuple and the other
* inserter's are covered by the combined tuple. It might be that
* we don't need to update at all.
*/
if (!brin_doupdate(idxRel, pagesPerRange, revmap, heapBlk,
buf, off, origtup, origsz, newtup, newsz,
samepage))
{
/* no luck; start over */
MemoryContextResetAndDeleteChildren(tupcxt);
continue;
}
}
/* success! */
break;
}
brinRevmapTerminate(revmap);
if (BufferIsValid(buf))
ReleaseBuffer(buf);
if (bdesc != NULL)
{
brin_free_desc(bdesc);
MemoryContextSwitchTo(oldcxt);
MemoryContextDelete(tupcxt);
}
return BoolGetDatum(false);
}
/*
* _bt_first() -- Find the first item in a scan.
*
* We need to be clever about the type of scan, the operation it's
* performing, and the tree ordering. We find the
* first item in the tree that satisfies the qualification
* associated with the scan descriptor. On exit, the page containing
* the current index tuple is read locked and pinned, and the scan's
* opaque data entry is updated to include the buffer.
*/
bool
_bt_first(IndexScanDesc scan, ScanDirection dir)
{
Relation rel = scan->indexRelation;
BTScanOpaque so = (BTScanOpaque) scan->opaque;
Buffer buf;
Page page;
BTStack stack;
OffsetNumber offnum;
BTItem btitem;
IndexTuple itup;
ItemPointer current;
BlockNumber blkno;
StrategyNumber strat;
bool res;
int32 result;
bool scanFromEnd;
bool continuescan;
ScanKey scankeys = NULL;
int keysCount = 0;
int *nKeyIs = NULL;
int i,
j;
StrategyNumber strat_total;
/*
* Order the scan keys in our canonical fashion and eliminate any
* redundant keys.
*/
_bt_orderkeys(scan);
/*
* Quit now if _bt_orderkeys() discovered that the scan keys can never
* be satisfied (eg, x == 1 AND x > 2).
*/
if (!so->qual_ok)
return false;
/*
* Examine the scan keys to discover where we need to start the scan.
*/
scanFromEnd = false;
strat_total = BTEqualStrategyNumber;
if (so->numberOfKeys > 0)
{
nKeyIs = (int *) palloc(so->numberOfKeys * sizeof(int));
for (i = 0; i < so->numberOfKeys; i++)
{
AttrNumber attno = so->keyData[i].sk_attno;
/* ignore keys for already-determined attrs */
if (attno <= keysCount)
continue;
/* if we didn't find a boundary for the preceding attr, quit */
if (attno > keysCount + 1)
break;
strat = _bt_getstrat(rel, attno,
so->keyData[i].sk_procedure);
/*
* Can we use this key as a starting boundary for this attr?
*
* We can use multiple keys if they look like, say, = >= = but we
* have to stop after accepting a > or < boundary.
*/
if (strat == strat_total ||
strat == BTEqualStrategyNumber)
nKeyIs[keysCount++] = i;
else if (ScanDirectionIsBackward(dir) &&
(strat == BTLessStrategyNumber ||
strat == BTLessEqualStrategyNumber))
{
nKeyIs[keysCount++] = i;
strat_total = strat;
if (strat == BTLessStrategyNumber)
break;
}
else if (ScanDirectionIsForward(dir) &&
(strat == BTGreaterStrategyNumber ||
strat == BTGreaterEqualStrategyNumber))
{
nKeyIs[keysCount++] = i;
strat_total = strat;
if (strat == BTGreaterStrategyNumber)
break;
}
}
if (keysCount == 0)
scanFromEnd = true;
}
else
scanFromEnd = true;
/* if we just need to walk down one edge of the tree, do that */
if (scanFromEnd)
{
if (nKeyIs)
pfree(nKeyIs);
return _bt_endpoint(scan, dir);
}
/*
* We want to start the scan somewhere within the index. Set up a
* scankey we can use to search for the correct starting point.
*/
scankeys = (ScanKey) palloc(keysCount * sizeof(ScanKeyData));
for (i = 0; i < keysCount; i++)
{
FmgrInfo *procinfo;
j = nKeyIs[i];
/*
* _bt_orderkeys disallows it, but it's place to add some code
* later
*/
if (so->keyData[j].sk_flags & SK_ISNULL)
{
pfree(nKeyIs);
pfree(scankeys);
elog(ERROR, "btree doesn't support is(not)null, yet");
return false;
}
procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC);
ScanKeyEntryInitializeWithInfo(scankeys + i,
so->keyData[j].sk_flags,
i + 1,
procinfo,
CurrentMemoryContext,
so->keyData[j].sk_argument);
}
if (nKeyIs)
pfree(nKeyIs);
current = &(scan->currentItemData);
/*
* Use the manufactured scan key to descend the tree and position
* ourselves on the target leaf page.
*/
stack = _bt_search(rel, keysCount, scankeys, &buf, BT_READ);
/* don't need to keep the stack around... */
_bt_freestack(stack);
if (!BufferIsValid(buf))
{
/* Only get here if index is completely empty */
ItemPointerSetInvalid(current);
so->btso_curbuf = InvalidBuffer;
pfree(scankeys);
return false;
}
/* remember which buffer we have pinned */
so->btso_curbuf = buf;
blkno = BufferGetBlockNumber(buf);
page = BufferGetPage(buf);
/* position to the precise item on the page */
offnum = _bt_binsrch(rel, buf, keysCount, scankeys);
ItemPointerSet(current, blkno, offnum);
/*
* At this point we are positioned at the first item >= scan key, or
* possibly at the end of a page on which all the existing items are
* less than the scan key and we know that everything on later pages
* is greater than or equal to scan key.
*
* We could step forward in the latter case, but that'd be a waste of
* time if we want to scan backwards. So, it's now time to examine
* the scan strategy to find the exact place to start the scan.
*
* Note: if _bt_step fails (meaning we fell off the end of the index in
* one direction or the other), we either return false (no matches) or
* call _bt_endpoint() to set up a scan starting at that index
* endpoint, as appropriate for the desired scan type.
*
* it's yet other place to add some code later for is(not)null ...
*/
switch (strat_total)
{
case BTLessStrategyNumber:
/*
* Back up one to arrive at last item < scankey
*/
if (!_bt_step(scan, &buf, BackwardScanDirection))
{
pfree(scankeys);
return false;
}
break;
case BTLessEqualStrategyNumber:
/*
* We need to find the last item <= scankey, so step forward
* till we find one > scankey, then step back one.
*/
if (offnum > PageGetMaxOffsetNumber(page))
{
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return _bt_endpoint(scan, dir);
}
}
for (;;)
{
offnum = ItemPointerGetOffsetNumber(current);
page = BufferGetPage(buf);
result = _bt_compare(rel, keysCount, scankeys, page, offnum);
if (result < 0)
break;
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return _bt_endpoint(scan, dir);
}
}
if (!_bt_step(scan, &buf, BackwardScanDirection))
{
pfree(scankeys);
return false;
}
break;
case BTEqualStrategyNumber:
/*
* Make sure we are on the first equal item; might have to
* step forward if currently at end of page.
*/
if (offnum > PageGetMaxOffsetNumber(page))
{
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return false;
}
offnum = ItemPointerGetOffsetNumber(current);
page = BufferGetPage(buf);
}
result = _bt_compare(rel, keysCount, scankeys, page, offnum);
if (result != 0)
goto nomatches; /* no equal items! */
/*
* If a backward scan was specified, need to start with last
* equal item not first one.
*/
if (ScanDirectionIsBackward(dir))
{
do
{
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return _bt_endpoint(scan, dir);
}
offnum = ItemPointerGetOffsetNumber(current);
page = BufferGetPage(buf);
result = _bt_compare(rel, keysCount, scankeys, page, offnum);
} while (result == 0);
if (!_bt_step(scan, &buf, BackwardScanDirection))
elog(ERROR, "equal items disappeared?");
}
break;
case BTGreaterEqualStrategyNumber:
/*
* We want the first item >= scankey, which is where we are...
* unless we're not anywhere at all...
*/
if (offnum > PageGetMaxOffsetNumber(page))
{
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return false;
}
}
break;
case BTGreaterStrategyNumber:
/*
* We want the first item > scankey, so make sure we are on an
* item and then step over any equal items.
*/
if (offnum > PageGetMaxOffsetNumber(page))
{
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return false;
}
offnum = ItemPointerGetOffsetNumber(current);
page = BufferGetPage(buf);
}
result = _bt_compare(rel, keysCount, scankeys, page, offnum);
while (result == 0)
{
if (!_bt_step(scan, &buf, ForwardScanDirection))
{
pfree(scankeys);
return false;
}
offnum = ItemPointerGetOffsetNumber(current);
page = BufferGetPage(buf);
result = _bt_compare(rel, keysCount, scankeys, page, offnum);
}
break;
}
/* okay, current item pointer for the scan is right */
offnum = ItemPointerGetOffsetNumber(current);
page = BufferGetPage(buf);
btitem = (BTItem) PageGetItem(page, PageGetItemId(page, offnum));
itup = &btitem->bti_itup;
/* is the first item actually acceptable? */
if (_bt_checkkeys(scan, itup, dir, &continuescan))
{
/* yes, return it */
scan->xs_ctup.t_self = itup->t_tid;
res = true;
}
else if (continuescan)
{
/* no, but there might be another one that is */
res = _bt_next(scan, dir);
}
else
{
/* no tuples in the index match this scan key */
nomatches:
ItemPointerSetInvalid(current);
so->btso_curbuf = InvalidBuffer;
_bt_relbuf(rel, buf);
res = false;
}
pfree(scankeys);
return res;
}
/*
* Fetch local cache of AM-specific info about the index, initializing it
* if necessary
*/
SpGistCache *
spgGetCache(Relation index)
{
SpGistCache *cache;
if (index->rd_amcache == NULL)
{
Oid atttype;
spgConfigIn in;
FmgrInfo *procinfo;
Buffer metabuffer;
SpGistMetaPageData *metadata;
cache = MemoryContextAllocZero(index->rd_indexcxt,
sizeof(SpGistCache));
/* SPGiST doesn't support multi-column indexes */
Assert(index->rd_att->natts == 1);
/*
* Get the actual data type of the indexed column from the index
* tupdesc. We pass this to the opclass config function so that
* polymorphic opclasses are possible.
*/
atttype = index->rd_att->attrs[0]->atttypid;
/* Call the config function to get config info for the opclass */
in.attType = atttype;
procinfo = index_getprocinfo(index, 1, SPGIST_CONFIG_PROC);
FunctionCall2Coll(procinfo,
index->rd_indcollation[0],
PointerGetDatum(&in),
PointerGetDatum(&cache->config));
/* Get the information we need about each relevant datatype */
fillTypeDesc(&cache->attType, atttype);
fillTypeDesc(&cache->attPrefixType, cache->config.prefixType);
fillTypeDesc(&cache->attLabelType, cache->config.labelType);
/* Last, get the lastUsedPages data from the metapage */
metabuffer = ReadBuffer(index, SPGIST_METAPAGE_BLKNO);
LockBuffer(metabuffer, BUFFER_LOCK_SHARE);
metadata = SpGistPageGetMeta(BufferGetPage(metabuffer));
if (metadata->magicNumber != SPGIST_MAGIC_NUMBER)
elog(ERROR, "index \"%s\" is not an SP-GiST index",
RelationGetRelationName(index));
cache->lastUsedPages = metadata->lastUsedPages;
UnlockReleaseBuffer(metabuffer);
index->rd_amcache = (void *) cache;
}
else
{
/* assume it's up to date */
cache = (SpGistCache *) index->rd_amcache;
}
return cache;
}
/*
* _bt_first() -- Find the first item in a scan.
*
* We need to be clever about the direction of scan, the search
* conditions, and the tree ordering. We find the first item (or,
* if backwards scan, the last item) in the tree that satisfies the
* qualifications in the scan key. On success exit, the page containing
* the current index tuple is pinned but not locked, and data about
* the matching tuple(s) on the page has been loaded into so->currPos.
* scan->xs_ctup.t_self is set to the heap TID of the current tuple,
* and if requested, scan->xs_itup points to a copy of the index tuple.
*
* If there are no matching items in the index, we return FALSE, with no
* pins or locks held.
*
* Note that scan->keyData[], and the so->keyData[] scankey built from it,
* are both search-type scankeys (see nbtree/README for more about this).
* Within this routine, we build a temporary insertion-type scankey to use
* in locating the scan start position.
*/
bool
_bt_first(IndexScanDesc scan, ScanDirection dir)
{
Relation rel = scan->indexRelation;
BTScanOpaque so = (BTScanOpaque) scan->opaque;
Buffer buf;
BTStack stack;
OffsetNumber offnum;
StrategyNumber strat;
bool nextkey;
bool goback;
ScanKey startKeys[INDEX_MAX_KEYS];
ScanKeyData scankeys[INDEX_MAX_KEYS];
ScanKeyData notnullkeys[INDEX_MAX_KEYS];
int keysCount = 0;
int i;
StrategyNumber strat_total;
BTScanPosItem *currItem;
pgstat_count_index_scan(rel);
/*
* Examine the scan keys and eliminate any redundant keys; also mark the
* keys that must be matched to continue the scan.
*/
_bt_preprocess_keys(scan);
/*
* Quit now if _bt_preprocess_keys() discovered that the scan keys can
* never be satisfied (eg, x == 1 AND x > 2).
*/
if (!so->qual_ok)
return false;
/*----------
* Examine the scan keys to discover where we need to start the scan.
*
* We want to identify the keys that can be used as starting boundaries;
* these are =, >, or >= keys for a forward scan or =, <, <= keys for
* a backwards scan. We can use keys for multiple attributes so long as
* the prior attributes had only =, >= (resp. =, <=) keys. Once we accept
* a > or < boundary or find an attribute with no boundary (which can be
* thought of as the same as "> -infinity"), we can't use keys for any
* attributes to its right, because it would break our simplistic notion
* of what initial positioning strategy to use.
*
* When the scan keys include cross-type operators, _bt_preprocess_keys
* may not be able to eliminate redundant keys; in such cases we will
* arbitrarily pick a usable one for each attribute. This is correct
* but possibly not optimal behavior. (For example, with keys like
* "x >= 4 AND x >= 5" we would elect to scan starting at x=4 when
* x=5 would be more efficient.) Since the situation only arises given
* a poorly-worded query plus an incomplete opfamily, live with it.
*
* When both equality and inequality keys appear for a single attribute
* (again, only possible when cross-type operators appear), we *must*
* select one of the equality keys for the starting point, because
* _bt_checkkeys() will stop the scan as soon as an equality qual fails.
* For example, if we have keys like "x >= 4 AND x = 10" and we elect to
* start at x=4, we will fail and stop before reaching x=10. If multiple
* equality quals survive preprocessing, however, it doesn't matter which
* one we use --- by definition, they are either redundant or
* contradictory.
*
* Any regular (not SK_SEARCHNULL) key implies a NOT NULL qualifier.
* If the index stores nulls at the end of the index we'll be starting
* from, and we have no boundary key for the column (which means the key
* we deduced NOT NULL from is an inequality key that constrains the other
* end of the index), then we cons up an explicit SK_SEARCHNOTNULL key to
* use as a boundary key. If we didn't do this, we might find ourselves
* traversing a lot of null entries at the start of the scan.
*
* In this loop, row-comparison keys are treated the same as keys on their
* first (leftmost) columns. We'll add on lower-order columns of the row
* comparison below, if possible.
*
* The selected scan keys (at most one per index column) are remembered by
* storing their addresses into the local startKeys[] array.
*----------
*/
strat_total = BTEqualStrategyNumber;
if (so->numberOfKeys > 0)
{
AttrNumber curattr;
ScanKey chosen;
ScanKey impliesNN;
ScanKey cur;
/*
* chosen is the so-far-chosen key for the current attribute, if any.
* We don't cast the decision in stone until we reach keys for the
* next attribute.
*/
curattr = 1;
chosen = NULL;
/* Also remember any scankey that implies a NOT NULL constraint */
impliesNN = NULL;
/*
* Loop iterates from 0 to numberOfKeys inclusive; we use the last
* pass to handle after-last-key processing. Actual exit from the
* loop is at one of the "break" statements below.
*/
for (cur = so->keyData, i = 0;; cur++, i++)
{
if (i >= so->numberOfKeys || cur->sk_attno != curattr)
{
/*
* Done looking at keys for curattr. If we didn't find a
* usable boundary key, see if we can deduce a NOT NULL key.
*/
if (chosen == NULL && impliesNN != NULL &&
((impliesNN->sk_flags & SK_BT_NULLS_FIRST) ?
ScanDirectionIsForward(dir) :
ScanDirectionIsBackward(dir)))
{
/* Yes, so build the key in notnullkeys[keysCount] */
chosen = ¬nullkeys[keysCount];
ScanKeyEntryInitialize(chosen,
(SK_SEARCHNOTNULL | SK_ISNULL |
(impliesNN->sk_flags &
(SK_BT_DESC | SK_BT_NULLS_FIRST))),
curattr,
((impliesNN->sk_flags & SK_BT_NULLS_FIRST) ?
BTGreaterStrategyNumber :
BTLessStrategyNumber),
InvalidOid,
InvalidOid,
InvalidOid,
(Datum) 0);
}
/*
* If we still didn't find a usable boundary key, quit; else
* save the boundary key pointer in startKeys.
*/
if (chosen == NULL)
break;
startKeys[keysCount++] = chosen;
/*
* Adjust strat_total, and quit if we have stored a > or <
* key.
*/
strat = chosen->sk_strategy;
if (strat != BTEqualStrategyNumber)
{
strat_total = strat;
if (strat == BTGreaterStrategyNumber ||
strat == BTLessStrategyNumber)
break;
}
/*
* Done if that was the last attribute, or if next key is not
* in sequence (implying no boundary key is available for the
* next attribute).
*/
if (i >= so->numberOfKeys ||
cur->sk_attno != curattr + 1)
break;
/*
* Reset for next attr.
*/
curattr = cur->sk_attno;
chosen = NULL;
impliesNN = NULL;
}
/*
* Can we use this key as a starting boundary for this attr?
*
* If not, does it imply a NOT NULL constraint? (Because
* SK_SEARCHNULL keys are always assigned BTEqualStrategyNumber,
* *any* inequality key works for that; we need not test.)
*/
switch (cur->sk_strategy)
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
if (chosen == NULL)
{
if (ScanDirectionIsBackward(dir))
chosen = cur;
else
impliesNN = cur;
}
break;
case BTEqualStrategyNumber:
/* override any non-equality choice */
chosen = cur;
break;
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
if (chosen == NULL)
{
if (ScanDirectionIsForward(dir))
chosen = cur;
else
impliesNN = cur;
}
break;
}
}
}
/*
* If we found no usable boundary keys, we have to start from one end of
* the tree. Walk down that edge to the first or last key, and scan from
* there.
*/
if (keysCount == 0)
return _bt_endpoint(scan, dir);
/*
* We want to start the scan somewhere within the index. Set up an
* insertion scankey we can use to search for the boundary point we
* identified above. The insertion scankey is built in the local
* scankeys[] array, using the keys identified by startKeys[].
*/
Assert(keysCount <= INDEX_MAX_KEYS);
for (i = 0; i < keysCount; i++)
{
ScanKey cur = startKeys[i];
Assert(cur->sk_attno == i + 1);
if (cur->sk_flags & SK_ROW_HEADER)
{
/*
* Row comparison header: look to the first row member instead.
*
* The member scankeys are already in insertion format (ie, they
* have sk_func = 3-way-comparison function), but we have to watch
* out for nulls, which _bt_preprocess_keys didn't check. A null
* in the first row member makes the condition unmatchable, just
* like qual_ok = false.
*/
ScanKey subkey = (ScanKey) DatumGetPointer(cur->sk_argument);
Assert(subkey->sk_flags & SK_ROW_MEMBER);
if (subkey->sk_flags & SK_ISNULL)
return false;
memcpy(scankeys + i, subkey, sizeof(ScanKeyData));
/*
* If the row comparison is the last positioning key we accepted,
* try to add additional keys from the lower-order row members.
* (If we accepted independent conditions on additional index
* columns, we use those instead --- doesn't seem worth trying to
* determine which is more restrictive.) Note that this is OK
* even if the row comparison is of ">" or "<" type, because the
* condition applied to all but the last row member is effectively
* ">=" or "<=", and so the extra keys don't break the positioning
* scheme. But, by the same token, if we aren't able to use all
* the row members, then the part of the row comparison that we
* did use has to be treated as just a ">=" or "<=" condition, and
* so we'd better adjust strat_total accordingly.
*/
if (i == keysCount - 1)
{
bool used_all_subkeys = false;
Assert(!(subkey->sk_flags & SK_ROW_END));
for (;;)
{
subkey++;
Assert(subkey->sk_flags & SK_ROW_MEMBER);
if (subkey->sk_attno != keysCount + 1)
break; /* out-of-sequence, can't use it */
if (subkey->sk_strategy != cur->sk_strategy)
break; /* wrong direction, can't use it */
if (subkey->sk_flags & SK_ISNULL)
break; /* can't use null keys */
Assert(keysCount < INDEX_MAX_KEYS);
memcpy(scankeys + keysCount, subkey, sizeof(ScanKeyData));
keysCount++;
if (subkey->sk_flags & SK_ROW_END)
{
used_all_subkeys = true;
break;
}
}
if (!used_all_subkeys)
{
switch (strat_total)
{
case BTLessStrategyNumber:
strat_total = BTLessEqualStrategyNumber;
break;
case BTGreaterStrategyNumber:
strat_total = BTGreaterEqualStrategyNumber;
break;
}
}
break; /* done with outer loop */
}
}
else
{
/*
* Ordinary comparison key. Transform the search-style scan key
* to an insertion scan key by replacing the sk_func with the
* appropriate btree comparison function.
*
* If scankey operator is not a cross-type comparison, we can use
* the cached comparison function; otherwise gotta look it up in
* the catalogs. (That can't lead to infinite recursion, since no
* indexscan initiated by syscache lookup will use cross-data-type
* operators.)
*
* We support the convention that sk_subtype == InvalidOid means
* the opclass input type; this is a hack to simplify life for
* ScanKeyInit().
*/
if (cur->sk_subtype == rel->rd_opcintype[i] ||
cur->sk_subtype == InvalidOid)
{
FmgrInfo *procinfo;
procinfo = index_getprocinfo(rel, cur->sk_attno, BTORDER_PROC);
ScanKeyEntryInitializeWithInfo(scankeys + i,
cur->sk_flags,
cur->sk_attno,
InvalidStrategy,
cur->sk_subtype,
cur->sk_collation,
procinfo,
cur->sk_argument);
}
else
{
RegProcedure cmp_proc;
cmp_proc = get_opfamily_proc(rel->rd_opfamily[i],
rel->rd_opcintype[i],
cur->sk_subtype,
BTORDER_PROC);
if (!RegProcedureIsValid(cmp_proc))
elog(ERROR, "missing support function %d(%u,%u) for attribute %d of index \"%s\"",
BTORDER_PROC, rel->rd_opcintype[i], cur->sk_subtype,
cur->sk_attno, RelationGetRelationName(rel));
ScanKeyEntryInitialize(scankeys + i,
cur->sk_flags,
cur->sk_attno,
InvalidStrategy,
cur->sk_subtype,
cur->sk_collation,
cmp_proc,
cur->sk_argument);
}
}
}
/*----------
* Examine the selected initial-positioning strategy to determine exactly
* where we need to start the scan, and set flag variables to control the
* code below.
*
* If nextkey = false, _bt_search and _bt_binsrch will locate the first
* item >= scan key. If nextkey = true, they will locate the first
* item > scan key.
*
* If goback = true, we will then step back one item, while if
* goback = false, we will start the scan on the located item.
*----------
*/
switch (strat_total)
{
case BTLessStrategyNumber:
/*
* Find first item >= scankey, then back up one to arrive at last
* item < scankey. (Note: this positioning strategy is only used
* for a backward scan, so that is always the correct starting
* position.)
*/
nextkey = false;
goback = true;
break;
case BTLessEqualStrategyNumber:
/*
* Find first item > scankey, then back up one to arrive at last
* item <= scankey. (Note: this positioning strategy is only used
* for a backward scan, so that is always the correct starting
* position.)
*/
nextkey = true;
goback = true;
break;
case BTEqualStrategyNumber:
/*
* If a backward scan was specified, need to start with last equal
* item not first one.
*/
if (ScanDirectionIsBackward(dir))
{
/*
* This is the same as the <= strategy. We will check at the
* end whether the found item is actually =.
*/
nextkey = true;
goback = true;
}
else
{
/*
* This is the same as the >= strategy. We will check at the
* end whether the found item is actually =.
*/
nextkey = false;
goback = false;
}
break;
case BTGreaterEqualStrategyNumber:
/*
* Find first item >= scankey. (This is only used for forward
* scans.)
*/
nextkey = false;
goback = false;
break;
case BTGreaterStrategyNumber:
/*
* Find first item > scankey. (This is only used for forward
* scans.)
*/
nextkey = true;
goback = false;
break;
default:
/* can't get here, but keep compiler quiet */
elog(ERROR, "unrecognized strat_total: %d", (int) strat_total);
return false;
}
/*
* Use the manufactured insertion scan key to descend the tree and
* position ourselves on the target leaf page.
*/
stack = _bt_search(rel, keysCount, scankeys, nextkey, &buf, BT_READ);
/* don't need to keep the stack around... */
_bt_freestack(stack);
/* remember which buffer we have pinned, if any */
so->currPos.buf = buf;
if (!BufferIsValid(buf))
{
/*
* We only get here if the index is completely empty. Lock relation
* because nothing finer to lock exists.
*/
PredicateLockRelation(rel, scan->xs_snapshot);
return false;
}
else
PredicateLockPage(rel, BufferGetBlockNumber(buf),
scan->xs_snapshot);
/* initialize moreLeft/moreRight appropriately for scan direction */
if (ScanDirectionIsForward(dir))
{
so->currPos.moreLeft = false;
so->currPos.moreRight = true;
}
else
{
so->currPos.moreLeft = true;
so->currPos.moreRight = false;
}
so->numKilled = 0; /* just paranoia */
so->markItemIndex = -1; /* ditto */
/* position to the precise item on the page */
offnum = _bt_binsrch(rel, buf, keysCount, scankeys, nextkey);
/*
* If nextkey = false, we are positioned at the first item >= scan key, or
* possibly at the end of a page on which all the existing items are less
* than the scan key and we know that everything on later pages is greater
* than or equal to scan key.
*
* If nextkey = true, we are positioned at the first item > scan key, or
* possibly at the end of a page on which all the existing items are less
* than or equal to the scan key and we know that everything on later
* pages is greater than scan key.
*
* The actually desired starting point is either this item or the prior
* one, or in the end-of-page case it's the first item on the next page or
* the last item on this page. Adjust the starting offset if needed. (If
* this results in an offset before the first item or after the last one,
* _bt_readpage will report no items found, and then we'll step to the
* next page as needed.)
*/
if (goback)
offnum = OffsetNumberPrev(offnum);
/*
* Now load data from the first page of the scan.
*/
if (!_bt_readpage(scan, dir, offnum))
{
/*
* There's no actually-matching data on this page. Try to advance to
* the next page. Return false if there's no matching data at all.
*/
if (!_bt_steppage(scan, dir))
return false;
}
/* Drop the lock, but not pin, on the current page */
LockBuffer(so->currPos.buf, BUFFER_LOCK_UNLOCK);
/* OK, itemIndex says what to return */
currItem = &so->currPos.items[so->currPos.itemIndex];
scan->xs_ctup.t_self = currItem->heapTid;
if (scan->xs_want_itup)
scan->xs_itup = (IndexTuple) (so->currTuples + currItem->tupleOffset);
return true;
}
/*
* A tuple in the heap is being inserted. To keep a brin index up to date,
* we need to obtain the relevant index tuple and compare its stored values
* with those of the new tuple. If the tuple values are not consistent with
* the summary tuple, we need to update the index tuple.
*
* If autosummarization is enabled, check if we need to summarize the previous
* page range.
*
* If the range is not currently summarized (i.e. the revmap returns NULL for
* it), there's nothing to do for this tuple.
*/
bool
brininsert(Relation idxRel, Datum *values, bool *nulls,
ItemPointer heaptid, Relation heapRel,
IndexUniqueCheck checkUnique,
IndexInfo *indexInfo)
{
BlockNumber pagesPerRange;
BlockNumber origHeapBlk;
BlockNumber heapBlk;
BrinDesc *bdesc = (BrinDesc *) indexInfo->ii_AmCache;
BrinRevmap *revmap;
Buffer buf = InvalidBuffer;
MemoryContext tupcxt = NULL;
MemoryContext oldcxt = CurrentMemoryContext;
bool autosummarize = BrinGetAutoSummarize(idxRel);
revmap = brinRevmapInitialize(idxRel, &pagesPerRange, NULL);
/*
* origHeapBlk is the block number where the insertion occurred. heapBlk
* is the first block in the corresponding page range.
*/
origHeapBlk = ItemPointerGetBlockNumber(heaptid);
heapBlk = (origHeapBlk / pagesPerRange) * pagesPerRange;
for (;;)
{
bool need_insert = false;
OffsetNumber off;
BrinTuple *brtup;
BrinMemTuple *dtup;
int keyno;
CHECK_FOR_INTERRUPTS();
/*
* If auto-summarization is enabled and we just inserted the first
* tuple into the first block of a new non-first page range, request a
* summarization run of the previous range.
*/
if (autosummarize &&
heapBlk > 0 &&
heapBlk == origHeapBlk &&
ItemPointerGetOffsetNumber(heaptid) == FirstOffsetNumber)
{
BlockNumber lastPageRange = heapBlk - 1;
BrinTuple *lastPageTuple;
lastPageTuple =
brinGetTupleForHeapBlock(revmap, lastPageRange, &buf, &off,
NULL, BUFFER_LOCK_SHARE, NULL);
if (!lastPageTuple)
{
bool recorded;
recorded = AutoVacuumRequestWork(AVW_BRINSummarizeRange,
RelationGetRelid(idxRel),
lastPageRange);
if (!recorded)
ereport(LOG,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("request for BRIN range summarization for index \"%s\" page %u was not recorded",
RelationGetRelationName(idxRel),
lastPageRange)));
}
else
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
}
brtup = brinGetTupleForHeapBlock(revmap, heapBlk, &buf, &off,
NULL, BUFFER_LOCK_SHARE, NULL);
/* if range is unsummarized, there's nothing to do */
if (!brtup)
break;
/* First time through in this statement? */
if (bdesc == NULL)
{
MemoryContextSwitchTo(indexInfo->ii_Context);
bdesc = brin_build_desc(idxRel);
indexInfo->ii_AmCache = (void *) bdesc;
MemoryContextSwitchTo(oldcxt);
}
/* First time through in this brininsert call? */
if (tupcxt == NULL)
{
tupcxt = AllocSetContextCreate(CurrentMemoryContext,
"brininsert cxt",
ALLOCSET_DEFAULT_SIZES);
MemoryContextSwitchTo(tupcxt);
}
dtup = brin_deform_tuple(bdesc, brtup, NULL);
/*
* Compare the key values of the new tuple to the stored index values;
* our deformed tuple will get updated if the new tuple doesn't fit
* the original range (note this means we can't break out of the loop
* early). Make a note of whether this happens, so that we know to
* insert the modified tuple later.
*/
for (keyno = 0; keyno < bdesc->bd_tupdesc->natts; keyno++)
{
Datum result;
BrinValues *bval;
FmgrInfo *addValue;
bval = &dtup->bt_columns[keyno];
addValue = index_getprocinfo(idxRel, keyno + 1,
BRIN_PROCNUM_ADDVALUE);
result = FunctionCall4Coll(addValue,
idxRel->rd_indcollation[keyno],
PointerGetDatum(bdesc),
PointerGetDatum(bval),
values[keyno],
nulls[keyno]);
/* if that returned true, we need to insert the updated tuple */
need_insert |= DatumGetBool(result);
}
if (!need_insert)
{
/*
* The tuple is consistent with the new values, so there's nothing
* to do.
*/
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
}
else
{
Page page = BufferGetPage(buf);
ItemId lp = PageGetItemId(page, off);
Size origsz;
BrinTuple *origtup;
Size newsz;
BrinTuple *newtup;
bool samepage;
/*
* Make a copy of the old tuple, so that we can compare it after
* re-acquiring the lock.
*/
origsz = ItemIdGetLength(lp);
origtup = brin_copy_tuple(brtup, origsz, NULL, NULL);
/*
* Before releasing the lock, check if we can attempt a same-page
* update. Another process could insert a tuple concurrently in
* the same page though, so downstream we must be prepared to cope
* if this turns out to not be possible after all.
*/
newtup = brin_form_tuple(bdesc, heapBlk, dtup, &newsz);
samepage = brin_can_do_samepage_update(buf, origsz, newsz);
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
/*
* Try to update the tuple. If this doesn't work for whatever
* reason, we need to restart from the top; the revmap might be
* pointing at a different tuple for this block now, so we need to
* recompute to ensure both our new heap tuple and the other
* inserter's are covered by the combined tuple. It might be that
* we don't need to update at all.
*/
if (!brin_doupdate(idxRel, pagesPerRange, revmap, heapBlk,
buf, off, origtup, origsz, newtup, newsz,
samepage))
{
/* no luck; start over */
MemoryContextResetAndDeleteChildren(tupcxt);
continue;
}
}
/* success! */
break;
}
brinRevmapTerminate(revmap);
if (BufferIsValid(buf))
ReleaseBuffer(buf);
MemoryContextSwitchTo(oldcxt);
if (tupcxt != NULL)
MemoryContextDelete(tupcxt);
return false;
}