/*
* CopyShardInterval copies fields from the specified source ShardInterval
* into the fields of the provided destination ShardInterval.
*/
void
CopyShardInterval(ShardInterval *srcInterval, ShardInterval *destInterval)
{
destInterval->type = srcInterval->type;
destInterval->relationId = srcInterval->relationId;
destInterval->storageType = srcInterval->storageType;
destInterval->valueTypeId = srcInterval->valueTypeId;
destInterval->valueTypeLen = srcInterval->valueTypeLen;
destInterval->valueByVal = srcInterval->valueByVal;
destInterval->minValueExists = srcInterval->minValueExists;
destInterval->maxValueExists = srcInterval->maxValueExists;
destInterval->shardId = srcInterval->shardId;
destInterval->minValue = 0;
if (destInterval->minValueExists)
{
destInterval->minValue = datumCopy(srcInterval->minValue,
srcInterval->valueByVal,
srcInterval->valueTypeLen);
}
destInterval->maxValue = 0;
if (destInterval->maxValueExists)
{
destInterval->maxValue = datumCopy(srcInterval->maxValue,
srcInterval->valueByVal,
srcInterval->valueTypeLen);
}
}
void setHstoreFromDatum(lua_State *L, Datum datum)
{
Lua_Hstore * strg;
BEGINLUA;
strg = (Lua_Hstore *)lua_newuserdata(L, sizeof(Lua_Hstore));
MTOLUA(L);
datum = datumCopy(datum, hs_type.byval, hs_type.len);
MTOPG;
strg->hstore = DatumGetHStoreP(datum);
strg->datum = datum;
strg->issync = 1;
strg->havetodel = 1;
lua_pushlightuserdata(L, strg);
lua_newtable(L);
lua_settable(L, LUA_REGISTRYINDEX);
luaP_getfield(L, hstore_type_name);
lua_setmetatable(L, -2);
ENDLUAV(1);
}
/*
* Copy a ParamListInfo structure.
*
* The result is allocated in CurrentMemoryContext.
*/
ParamListInfo
copyParamList(ParamListInfo from)
{
ParamListInfo retval;
Size size;
int i;
if (from == NULL || from->numParams <= 0)
return NULL;
/* sizeof(ParamListInfoData) includes the first array element */
size = sizeof(ParamListInfoData) +
(from->numParams - 1) *sizeof(ParamExternData);
retval = (ParamListInfo) palloc(size);
memcpy(retval, from, size);
/*
* Flat-copy is not good enough for pass-by-ref data values, so make a
* pass over the array to copy those.
*/
for (i = 0; i < retval->numParams; i++)
{
ParamExternData *prm = &retval->params[i];
int16 typLen;
bool typByVal;
if (prm->isnull || !OidIsValid(prm->ptype))
continue;
get_typlenbyval(prm->ptype, &typLen, &typByVal);
prm->value = datumCopy(prm->value, typByVal, typLen);
}
return retval;
}
/*-------------------------------------------------------------------------
* datumTransfer
*
* Transfer a non-NULL datum into the current memory context.
*
* This is equivalent to datumCopy() except when the datum is a read-write
* pointer to an expanded object. In that case we merely reparent the object
* into the current context, and return its standard R/W pointer (in case the
* given one is a transient pointer of shorter lifespan).
*-------------------------------------------------------------------------
*/
Datum
datumTransfer(Datum value, bool typByVal, int typLen)
{
if (!typByVal && typLen == -1 &&
VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(value)))
value = TransferExpandedObject(value, CurrentMemoryContext);
else
value = datumCopy(value, typByVal, typLen);
return value;
}
/*
* This is basically the same as datumCopy(), but extended to count
* palloc'd space in accum->allocatedMemory.
*/
static Datum
getDatumCopy(BuildAccumulator *accum, OffsetNumber attnum, Datum value)
{
Form_pg_attribute att = accum->ginstate->origTupdesc->attrs[attnum - 1];
Datum res;
if (att->attbyval)
res = value;
else
{
res = datumCopy(value, false, att->attlen);
accum->allocatedMemory += GetMemoryChunkSpace(DatumGetPointer(res));
}
return res;
}
Datum anyold_transfn(PG_FUNCTION_ARGS)
{
Oid type;
Datum state;
MemoryContext aggcontext,
oldcontext;
int16 typlen;
bool typbyval;
char typalign;
if (!AggCheckCallContext(fcinfo, &aggcontext))
{
/* cannot be called directly because of internal-type argument */
elog(ERROR, "anyold_transfn called in non-aggregate context");
}
if (PG_ARGISNULL(0))
{
if (PG_ARGISNULL(1))
PG_RETURN_NULL();
/* First non-null value --- initialize */
oldcontext = MemoryContextSwitchTo(aggcontext);
type = get_fn_expr_argtype(fcinfo->flinfo, 1);
if (type == InvalidOid)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not determine input data type")));
get_typlenbyvalalign(type,
&typlen,
&typbyval,
&typalign);
/* Copy initial value */
if (typlen == -1)
state = PointerGetDatum(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
else
state = datumCopy(PG_GETARG_DATUM(1), typbyval, typlen);
MemoryContextSwitchTo(oldcontext);
}
else
{
state = PG_GETARG_DATUM(0);
}
PG_RETURN_DATUM(state);
}
/*
* Get datum representations of the attoptions field in pg_attribute_encoding
* for the given relation.
*/
Datum *
get_rel_attoptions(Oid relid, AttrNumber max_attno)
{
Form_pg_attribute attform;
HeapTuple tuple;
cqContext cqc;
cqContext *pcqCtx;
Datum *dats;
Relation pgae = heap_open(AttributeEncodingRelationId,
AccessShareLock);
/* used for attbyval and len below */
attform = pgae->rd_att->attrs[Anum_pg_attribute_encoding_attoptions - 1];
dats = palloc0(max_attno * sizeof(Datum));
pcqCtx = caql_beginscan(
caql_addrel(cqclr(&cqc), pgae),
cql("SELECT * FROM pg_attribute_encoding "
" WHERE attrelid = :1 ",
ObjectIdGetDatum(relid)));
while (HeapTupleIsValid(tuple = caql_getnext(pcqCtx)))
{
Form_pg_attribute_encoding a =
(Form_pg_attribute_encoding)GETSTRUCT(tuple);
int16 attnum = a->attnum;
Datum attoptions;
bool isnull;
Insist(attnum > 0 && attnum <= max_attno);
attoptions = heap_getattr(tuple, Anum_pg_attribute_encoding_attoptions,
RelationGetDescr(pgae), &isnull);
Insist(!isnull);
dats[attnum - 1] = datumCopy(attoptions,
attform->attbyval,
attform->attlen);
}
caql_endscan(pcqCtx);
heap_close(pgae, AccessShareLock);
return dats;
}
static void
argm_copy_datum(bool is_null, Datum src, ArgmDatumWithType *dest, bool free)
{
if (free && !dest->typbyval && !dest->is_null)
pfree(DatumGetPointer(dest->value));
if (is_null)
dest->is_null = true;
else {
dest->is_null = false;
if (dest->typlen == -1)
dest->value = PointerGetDatum(PG_DETOAST_DATUM_COPY(src));
else
dest->value = datumCopy(src, dest->typbyval, dest->typlen);
}
}
/*
* Copy a ParamListInfo structure.
*
* The result is allocated in CurrentMemoryContext.
*
* Note: the intent of this function is to make a static, self-contained
* set of parameter values. If dynamic parameter hooks are present, we
* intentionally do not copy them into the result. Rather, we forcibly
* instantiate all available parameter values and copy the datum values.
*/
ParamListInfo
copyParamList(ParamListInfo from)
{
ParamListInfo retval;
Size size;
int i;
if (from == NULL || from->numParams <= 0)
return NULL;
/* sizeof(ParamListInfoData) includes the first array element */
size = sizeof(ParamListInfoData) +
(from->numParams - 1) * sizeof(ParamExternData);
retval = (ParamListInfo) palloc(size);
retval->paramFetch = NULL;
retval->paramFetchArg = NULL;
retval->parserSetup = NULL;
retval->parserSetupArg = NULL;
retval->numParams = from->numParams;
for (i = 0; i < from->numParams; i++)
{
ParamExternData *oprm = &from->params[i];
ParamExternData *nprm = &retval->params[i];
int16 typLen;
bool typByVal;
/* give hook a chance in case parameter is dynamic */
if (!OidIsValid(oprm->ptype) && from->paramFetch != NULL)
(*from->paramFetch) (from, i + 1);
/* flat-copy the parameter info */
*nprm = *oprm;
/* need datumCopy in case it's a pass-by-reference datatype */
if (nprm->isnull || !OidIsValid(nprm->ptype))
continue;
get_typlenbyval(nprm->ptype, &typLen, &typByVal);
nprm->value = datumCopy(nprm->value, typByVal, typLen);
}
return retval;
}
Datum
jsonb_numeric(PG_FUNCTION_ARGS)
{
Jsonb *j = PG_GETARG_JSONB(0);
if (JB_ROOT_IS_SCALAR(j))
{
JsonbValue *jv;
jv = getIthJsonbValueFromContainer(&j->root, 0);
if (jv->type == jbvNumeric)
PG_RETURN_DATUM(datumCopy(NumericGetDatum(jv->val.numeric), false,
-1));
}
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("%s cannot be converted to numeric",
JsonbToCString(NULL, &j->root, VARSIZE(j)))));
PG_RETURN_NULL();
}
Datum
spg_text_inner_consistent(PG_FUNCTION_ARGS)
{
spgInnerConsistentIn *in = (spgInnerConsistentIn *) PG_GETARG_POINTER(0);
spgInnerConsistentOut *out = (spgInnerConsistentOut *) PG_GETARG_POINTER(1);
StrategyNumber strategy = in->strategy;
text *inText;
int inSize;
int i;
text *reconstrText = NULL;
int maxReconstrLen = 0;
text *prefixText = NULL;
int prefixSize = 0;
/*
* If it's a collation-aware operator, but the collation is C, we can
* treat it as non-collation-aware.
*/
if (strategy > 10 &&
lc_collate_is_c(PG_GET_COLLATION()))
strategy -= 10;
inText = DatumGetTextPP(in->query);
inSize = VARSIZE_ANY_EXHDR(inText);
/*
* Reconstruct values represented at this tuple, including parent data,
* prefix of this tuple if any, and the node label if any. in->level
* should be the length of the previously reconstructed value, and the
* number of bytes added here is prefixSize or prefixSize + 1.
*
* Note: we assume that in->reconstructedValue isn't toasted and doesn't
* have a short varlena header. This is okay because it must have been
* created by a previous invocation of this routine, and we always emit
* long-format reconstructed values.
*/
Assert(in->level == 0 ? DatumGetPointer(in->reconstructedValue) == NULL :
VARSIZE_ANY_EXHDR(DatumGetPointer(in->reconstructedValue)) == in->level);
maxReconstrLen = in->level + 1;
if (in->hasPrefix)
{
prefixText = DatumGetTextPP(in->prefixDatum);
prefixSize = VARSIZE_ANY_EXHDR(prefixText);
maxReconstrLen += prefixSize;
}
reconstrText = palloc(VARHDRSZ + maxReconstrLen);
SET_VARSIZE(reconstrText, VARHDRSZ + maxReconstrLen);
if (in->level)
memcpy(VARDATA(reconstrText),
VARDATA(DatumGetPointer(in->reconstructedValue)),
in->level);
if (prefixSize)
memcpy(((char *) VARDATA(reconstrText)) + in->level,
VARDATA_ANY(prefixText),
prefixSize);
/* last byte of reconstrText will be filled in below */
/*
* Scan the child nodes. For each one, complete the reconstructed value
* and see if it's consistent with the query. If so, emit an entry into
* the output arrays.
*/
out->nodeNumbers = (int *) palloc(sizeof(int) * in->nNodes);
out->levelAdds = (int *) palloc(sizeof(int) * in->nNodes);
out->reconstructedValues = (Datum *) palloc(sizeof(Datum) * in->nNodes);
out->nNodes = 0;
for (i = 0; i < in->nNodes; i++)
{
uint8 nodeChar = DatumGetUInt8(in->nodeLabels[i]);
int thisLen;
int r;
bool res = false;
/* If nodeChar is zero, don't include it in data */
if (nodeChar == '\0')
thisLen = maxReconstrLen - 1;
else
{
((char *) VARDATA(reconstrText))[maxReconstrLen - 1] = nodeChar;
thisLen = maxReconstrLen;
}
r = memcmp(VARDATA(reconstrText), VARDATA_ANY(inText),
Min(inSize, thisLen));
switch (strategy)
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
if (r <= 0)
res = true;
break;
case BTEqualStrategyNumber:
if (r == 0 && inSize >= thisLen)
res = true;
break;
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
if (r >= 0)
res = true;
break;
case BTLessStrategyNumber + 10:
case BTLessEqualStrategyNumber + 10:
case BTGreaterEqualStrategyNumber + 10:
case BTGreaterStrategyNumber + 10:
/*
* with non-C collation we need to traverse whole tree :-(
*/
res = true;
break;
default:
elog(ERROR, "unrecognized strategy number: %d",
in->strategy);
break;
}
if (res)
{
out->nodeNumbers[out->nNodes] = i;
out->levelAdds[out->nNodes] = thisLen - in->level;
SET_VARSIZE(reconstrText, VARHDRSZ + thisLen);
out->reconstructedValues[out->nNodes] =
datumCopy(PointerGetDatum(reconstrText), false, -1);
out->nNodes++;
}
}
PG_RETURN_VOID();
}
/*
* SPI_cursor_open()
*
* Open a prepared SPI plan as a portal
*/
Portal
SPI_cursor_open(const char *name, void *plan,
Datum *Values, const char *Nulls,
bool read_only)
{
_SPI_plan *spiplan = (_SPI_plan *) plan;
List *qtlist = spiplan->qtlist;
List *ptlist = spiplan->ptlist;
Query *queryTree;
Plan *planTree;
ParamListInfo paramLI;
Snapshot snapshot;
MemoryContext oldcontext;
Portal portal;
int k;
/* Ensure that the plan contains only one query */
if (list_length(ptlist) != 1 || list_length(qtlist) != 1)
ereport(ERROR,
(errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
errmsg("cannot open multi-query plan as cursor")));
queryTree = (Query *) linitial((List *) linitial(qtlist));
planTree = (Plan *) linitial(ptlist);
/* Must be a query that returns tuples */
switch (queryTree->commandType)
{
case CMD_SELECT:
if (queryTree->into != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
errmsg("cannot open SELECT INTO query as cursor")));
break;
case CMD_UTILITY:
if (!UtilityReturnsTuples(queryTree->utilityStmt))
ereport(ERROR,
(errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
errmsg("cannot open non-SELECT query as cursor")));
break;
default:
ereport(ERROR,
(errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
errmsg("cannot open non-SELECT query as cursor")));
break;
}
/* Reset SPI result */
SPI_processed = 0;
SPI_tuptable = NULL;
_SPI_current->processed = 0;
_SPI_current->tuptable = NULL;
/* Create the portal */
if (name == NULL || name[0] == '\0')
{
/* Use a random nonconflicting name */
portal = CreateNewPortal();
}
else
{
/* In this path, error if portal of same name already exists */
portal = CreatePortal(name, false, false);
}
/* Switch to portals memory and copy the parsetree and plan to there */
oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
queryTree = copyObject(queryTree);
planTree = copyObject(planTree);
/* If the plan has parameters, set them up */
if (spiplan->nargs > 0)
{
paramLI = (ParamListInfo) palloc0((spiplan->nargs + 1) *
sizeof(ParamListInfoData));
for (k = 0; k < spiplan->nargs; k++)
{
paramLI[k].kind = PARAM_NUM;
paramLI[k].id = k + 1;
paramLI[k].ptype = spiplan->argtypes[k];
paramLI[k].isnull = (Nulls && Nulls[k] == 'n');
if (paramLI[k].isnull)
{
/* nulls just copy */
paramLI[k].value = Values[k];
}
else
{
/* pass-by-ref values must be copied into portal context */
int16 paramTypLen;
bool paramTypByVal;
get_typlenbyval(spiplan->argtypes[k],
¶mTypLen, ¶mTypByVal);
paramLI[k].value = datumCopy(Values[k],
paramTypByVal, paramTypLen);
}
}
paramLI[k].kind = PARAM_INVALID;
}
else
paramLI = NULL;
/*
* Set up the portal.
*/
PortalDefineQuery(portal,
NULL, /* unfortunately don't have sourceText */
"SELECT", /* nor the raw parse tree... */
list_make1(queryTree),
list_make1(planTree),
PortalGetHeapMemory(portal));
MemoryContextSwitchTo(oldcontext);
/*
* Set up options for portal.
*/
portal->cursorOptions &= ~(CURSOR_OPT_SCROLL | CURSOR_OPT_NO_SCROLL);
if (planTree == NULL || ExecSupportsBackwardScan(planTree))
portal->cursorOptions |= CURSOR_OPT_SCROLL;
else
portal->cursorOptions |= CURSOR_OPT_NO_SCROLL;
/*
* Set up the snapshot to use. (PortalStart will do CopySnapshot,
* so we skip that here.)
*/
if (read_only)
snapshot = ActiveSnapshot;
else
{
CommandCounterIncrement();
snapshot = GetTransactionSnapshot();
}
/*
* Start portal execution.
*/
PortalStart(portal, paramLI, snapshot);
Assert(portal->strategy == PORTAL_ONE_SELECT ||
portal->strategy == PORTAL_UTIL_SELECT);
/* Return the created portal */
return portal;
}
/*
* get_attstatsslot
*
* Extract the contents of a "slot" of a pg_statistic tuple.
* Returns TRUE if requested slot type was found, else FALSE.
*
* Unlike other routines in this file, this takes a pointer to an
* already-looked-up tuple in the pg_statistic cache. We do this since
* most callers will want to extract more than one value from the cache
* entry, and we don't want to repeat the cache lookup unnecessarily.
*
* statstuple: pg_statistics tuple to be examined.
* atttype: type OID of attribute (can be InvalidOid if values == NULL).
* atttypmod: typmod of attribute (can be 0 if values == NULL).
* reqkind: STAKIND code for desired statistics slot kind.
* reqop: STAOP value wanted, or InvalidOid if don't care.
* values, nvalues: if not NULL, the slot's stavalues are extracted.
* numbers, nnumbers: if not NULL, the slot's stanumbers are extracted.
*
* If assigned, values and numbers are set to point to palloc'd arrays.
* If the attribute type is pass-by-reference, the values referenced by
* the values array are themselves palloc'd. The palloc'd stuff can be
* freed by calling free_attstatsslot.
*/
bool
get_attstatsslot(HeapTuple statstuple,
Oid atttype, int32 atttypmod,
int reqkind, Oid reqop,
Datum **values, int *nvalues,
float4 **numbers, int *nnumbers)
{
Form_pg_statistic stats = (Form_pg_statistic) GETSTRUCT(statstuple);
int i,
j;
Datum val;
bool isnull;
ArrayType *statarray;
int narrayelem;
HeapTuple typeTuple;
Form_pg_type typeForm;
for (i = 0; i < STATISTIC_NUM_SLOTS; i++)
{
if ((&stats->stakind1)[i] == reqkind &&
(reqop == InvalidOid || (&stats->staop1)[i] == reqop))
break;
}
if (i >= STATISTIC_NUM_SLOTS)
return false; /* not there */
if (values)
{
val = SysCacheGetAttr(STATRELATT, statstuple,
Anum_pg_statistic_stavalues1 + i,
&isnull);
if (isnull)
elog(ERROR, "stavalues is null");
statarray = DatumGetArrayTypeP(val);
/* Need to get info about the array element type */
typeTuple = SearchSysCache(TYPEOID,
ObjectIdGetDatum(atttype),
0, 0, 0);
if (!HeapTupleIsValid(typeTuple))
elog(ERROR, "cache lookup failed for type %u", atttype);
typeForm = (Form_pg_type) GETSTRUCT(typeTuple);
/* Deconstruct array into Datum elements; NULLs not expected */
deconstruct_array(statarray,
atttype,
typeForm->typlen,
typeForm->typbyval,
typeForm->typalign,
values, NULL, nvalues);
/*
* If the element type is pass-by-reference, we now have a bunch of
* Datums that are pointers into the syscache value. Copy them to
* avoid problems if syscache decides to drop the entry.
*/
if (!typeForm->typbyval)
{
for (j = 0; j < *nvalues; j++)
{
(*values)[j] = datumCopy((*values)[j],
typeForm->typbyval,
typeForm->typlen);
}
}
ReleaseSysCache(typeTuple);
/*
* Free statarray if it's a detoasted copy.
*/
if ((Pointer) statarray != DatumGetPointer(val))
pfree(statarray);
}
if (numbers)
{
val = SysCacheGetAttr(STATRELATT, statstuple,
Anum_pg_statistic_stanumbers1 + i,
&isnull);
if (isnull)
elog(ERROR, "stanumbers is null");
statarray = DatumGetArrayTypeP(val);
/*
* We expect the array to be a 1-D float4 array; verify that. We don't
* need to use deconstruct_array() since the array data is just going
* to look like a C array of float4 values.
*/
narrayelem = ARR_DIMS(statarray)[0];
if (ARR_NDIM(statarray) != 1 || narrayelem <= 0 ||
ARR_HASNULL(statarray) ||
ARR_ELEMTYPE(statarray) != FLOAT4OID)
elog(ERROR, "stanumbers is not a 1-D float4 array");
*numbers = (float4 *) palloc(narrayelem * sizeof(float4));
memcpy(*numbers, ARR_DATA_PTR(statarray), narrayelem * sizeof(float4));
*nnumbers = narrayelem;
/*
* Free statarray if it's a detoasted copy.
*/
if ((Pointer) statarray != DatumGetPointer(val))
pfree(statarray);
}
return true;
}
Datum
spg_text_inner_consistent(PG_FUNCTION_ARGS)
{
spgInnerConsistentIn *in = (spgInnerConsistentIn *) PG_GETARG_POINTER(0);
spgInnerConsistentOut *out = (spgInnerConsistentOut *) PG_GETARG_POINTER(1);
bool collate_is_c = lc_collate_is_c(PG_GET_COLLATION());
text *reconstrText = NULL;
int maxReconstrLen = 0;
text *prefixText = NULL;
int prefixSize = 0;
int i;
/*
* Reconstruct values represented at this tuple, including parent data,
* prefix of this tuple if any, and the node label if it's non-dummy.
* in->level should be the length of the previously reconstructed value,
* and the number of bytes added here is prefixSize or prefixSize + 1.
*
* Note: we assume that in->reconstructedValue isn't toasted and doesn't
* have a short varlena header. This is okay because it must have been
* created by a previous invocation of this routine, and we always emit
* long-format reconstructed values.
*/
Assert(in->level == 0 ? DatumGetPointer(in->reconstructedValue) == NULL :
VARSIZE_ANY_EXHDR(DatumGetPointer(in->reconstructedValue)) == in->level);
maxReconstrLen = in->level + 1;
if (in->hasPrefix)
{
prefixText = DatumGetTextPP(in->prefixDatum);
prefixSize = VARSIZE_ANY_EXHDR(prefixText);
maxReconstrLen += prefixSize;
}
reconstrText = palloc(VARHDRSZ + maxReconstrLen);
SET_VARSIZE(reconstrText, VARHDRSZ + maxReconstrLen);
if (in->level)
memcpy(VARDATA(reconstrText),
VARDATA(DatumGetPointer(in->reconstructedValue)),
in->level);
if (prefixSize)
memcpy(((char *) VARDATA(reconstrText)) + in->level,
VARDATA_ANY(prefixText),
prefixSize);
/* last byte of reconstrText will be filled in below */
/*
* Scan the child nodes. For each one, complete the reconstructed value
* and see if it's consistent with the query. If so, emit an entry into
* the output arrays.
*/
out->nodeNumbers = (int *) palloc(sizeof(int) * in->nNodes);
out->levelAdds = (int *) palloc(sizeof(int) * in->nNodes);
out->reconstructedValues = (Datum *) palloc(sizeof(Datum) * in->nNodes);
out->nNodes = 0;
for (i = 0; i < in->nNodes; i++)
{
int16 nodeChar = DatumGetInt16(in->nodeLabels[i]);
int thisLen;
bool res = true;
int j;
/* If nodeChar is a dummy value, don't include it in data */
if (nodeChar <= 0)
thisLen = maxReconstrLen - 1;
else
{
((unsigned char *) VARDATA(reconstrText))[maxReconstrLen - 1] = nodeChar;
thisLen = maxReconstrLen;
}
for (j = 0; j < in->nkeys; j++)
{
StrategyNumber strategy = in->scankeys[j].sk_strategy;
text *inText;
int inSize;
int r;
/*
* If it's a collation-aware operator, but the collation is C, we
* can treat it as non-collation-aware. With non-C collation we
* need to traverse whole tree :-( so there's no point in making
* any check here. (Note also that our reconstructed value may
* well end with a partial multibyte character, so that applying
* any encoding-sensitive test to it would be risky anyhow.)
*/
if (strategy > 10)
{
if (collate_is_c)
strategy -= 10;
else
continue;
}
inText = DatumGetTextPP(in->scankeys[j].sk_argument);
inSize = VARSIZE_ANY_EXHDR(inText);
r = memcmp(VARDATA(reconstrText), VARDATA_ANY(inText),
Min(inSize, thisLen));
switch (strategy)
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
if (r > 0)
res = false;
break;
case BTEqualStrategyNumber:
if (r != 0 || inSize < thisLen)
res = false;
break;
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
if (r < 0)
res = false;
break;
default:
elog(ERROR, "unrecognized strategy number: %d",
in->scankeys[j].sk_strategy);
break;
}
if (!res)
break; /* no need to consider remaining conditions */
}
if (res)
{
out->nodeNumbers[out->nNodes] = i;
out->levelAdds[out->nNodes] = thisLen - in->level;
SET_VARSIZE(reconstrText, VARHDRSZ + thisLen);
out->reconstructedValues[out->nNodes] =
datumCopy(PointerGetDatum(reconstrText), false, -1);
out->nNodes++;
}
}
PG_RETURN_VOID();
}
/*
* Examine the given index tuple (which contains partial status of a certain
* page range) by comparing it to the given value that comes from another heap
* tuple. If the new value is outside the min/max range specified by the
* existing tuple values, update the index tuple and return true. Otherwise,
* return false and do not modify in this case.
*/
Datum
brin_minmax_add_value(PG_FUNCTION_ARGS)
{
BrinDesc *bdesc = (BrinDesc *) PG_GETARG_POINTER(0);
BrinValues *column = (BrinValues *) PG_GETARG_POINTER(1);
Datum newval = PG_GETARG_DATUM(2);
bool isnull = PG_GETARG_DATUM(3);
Oid colloid = PG_GET_COLLATION();
FmgrInfo *cmpFn;
Datum compar;
bool updated = false;
Form_pg_attribute attr;
AttrNumber attno;
/*
* If the new value is null, we record that we saw it if it's the first
* one; otherwise, there's nothing to do.
*/
if (isnull)
{
if (column->bv_hasnulls)
PG_RETURN_BOOL(false);
column->bv_hasnulls = true;
PG_RETURN_BOOL(true);
}
attno = column->bv_attno;
attr = bdesc->bd_tupdesc->attrs[attno - 1];
/*
* If the recorded value is null, store the new value (which we know to be
* not null) as both minimum and maximum, and we're done.
*/
if (column->bv_allnulls)
{
column->bv_values[0] = datumCopy(newval, attr->attbyval, attr->attlen);
column->bv_values[1] = datumCopy(newval, attr->attbyval, attr->attlen);
column->bv_allnulls = false;
PG_RETURN_BOOL(true);
}
/*
* Otherwise, need to compare the new value with the existing boundaries
* and update them accordingly. First check if it's less than the
* existing minimum.
*/
cmpFn = minmax_get_strategy_procinfo(bdesc, attno, attr->atttypid,
BTLessStrategyNumber);
compar = FunctionCall2Coll(cmpFn, colloid, newval, column->bv_values[0]);
if (DatumGetBool(compar))
{
if (!attr->attbyval)
pfree(DatumGetPointer(column->bv_values[0]));
column->bv_values[0] = datumCopy(newval, attr->attbyval, attr->attlen);
updated = true;
}
/*
* And now compare it to the existing maximum.
*/
cmpFn = minmax_get_strategy_procinfo(bdesc, attno, attr->atttypid,
BTGreaterStrategyNumber);
compar = FunctionCall2Coll(cmpFn, colloid, newval, column->bv_values[1]);
if (DatumGetBool(compar))
{
if (!attr->attbyval)
pfree(DatumGetPointer(column->bv_values[1]));
column->bv_values[1] = datumCopy(newval, attr->attbyval, attr->attlen);
updated = true;
}
PG_RETURN_BOOL(updated);
}
/*
* Given two BrinValues, update the first of them as a union of the summary
* values contained in both. The second one is untouched.
*/
Datum
brin_minmax_union(PG_FUNCTION_ARGS)
{
BrinDesc *bdesc = (BrinDesc *) PG_GETARG_POINTER(0);
BrinValues *col_a = (BrinValues *) PG_GETARG_POINTER(1);
BrinValues *col_b = (BrinValues *) PG_GETARG_POINTER(2);
Oid colloid = PG_GET_COLLATION();
AttrNumber attno;
Form_pg_attribute attr;
FmgrInfo *finfo;
bool needsadj;
Assert(col_a->bv_attno == col_b->bv_attno);
/* Adjust "hasnulls" */
if (!col_a->bv_hasnulls && col_b->bv_hasnulls)
col_a->bv_hasnulls = true;
/* If there are no values in B, there's nothing left to do */
if (col_b->bv_allnulls)
PG_RETURN_VOID();
attno = col_a->bv_attno;
attr = bdesc->bd_tupdesc->attrs[attno - 1];
/*
* Adjust "allnulls". If A doesn't have values, just copy the values
* from B into A, and we're done. We cannot run the operators in this
* case, because values in A might contain garbage. Note we already
* established that B contains values.
*/
if (col_a->bv_allnulls)
{
col_a->bv_allnulls = false;
col_a->bv_values[0] = datumCopy(col_b->bv_values[0],
attr->attbyval, attr->attlen);
col_a->bv_values[1] = datumCopy(col_b->bv_values[1],
attr->attbyval, attr->attlen);
PG_RETURN_VOID();
}
/* Adjust minimum, if B's min is less than A's min */
finfo = minmax_get_strategy_procinfo(bdesc, attno, attr->atttypid,
BTLessStrategyNumber);
needsadj = FunctionCall2Coll(finfo, colloid, col_b->bv_values[0],
col_a->bv_values[0]);
if (needsadj)
{
if (!attr->attbyval)
pfree(DatumGetPointer(col_a->bv_values[0]));
col_a->bv_values[0] = datumCopy(col_b->bv_values[0],
attr->attbyval, attr->attlen);
}
/* Adjust maximum, if B's max is greater than A's max */
finfo = minmax_get_strategy_procinfo(bdesc, attno, attr->atttypid,
BTGreaterStrategyNumber);
needsadj = FunctionCall2Coll(finfo, colloid, col_b->bv_values[1],
col_a->bv_values[1]);
if (needsadj)
{
if (!attr->attbyval)
pfree(DatumGetPointer(col_a->bv_values[1]));
col_a->bv_values[1] = datumCopy(col_b->bv_values[1],
attr->attbyval, attr->attlen);
}
PG_RETURN_VOID();
}
/*
* compute_array_stats() -- compute statistics for an array column
*
* This function computes statistics useful for determining selectivity of
* the array operators <@, &&, and @>. It is invoked by ANALYZE via the
* compute_stats hook after sample rows have been collected.
*
* We also invoke the standard compute_stats function, which will compute
* "scalar" statistics relevant to the btree-style array comparison operators.
* However, exact duplicates of an entire array may be rare despite many
* arrays sharing individual elements. This especially afflicts long arrays,
* which are also liable to lack all scalar statistics due to the low
* WIDTH_THRESHOLD used in analyze.c. So, in addition to the standard stats,
* we find the most common array elements and compute a histogram of distinct
* element counts.
*
* The algorithm used is Lossy Counting, as proposed in the paper "Approximate
* frequency counts over data streams" by G. S. Manku and R. Motwani, in
* Proceedings of the 28th International Conference on Very Large Data Bases,
* Hong Kong, China, August 2002, section 4.2. The paper is available at
* http://www.vldb.org/conf/2002/S10P03.pdf
*
* The Lossy Counting (aka LC) algorithm goes like this:
* Let s be the threshold frequency for an item (the minimum frequency we
* are interested in) and epsilon the error margin for the frequency. Let D
* be a set of triples (e, f, delta), where e is an element value, f is that
* element's frequency (actually, its current occurrence count) and delta is
* the maximum error in f. We start with D empty and process the elements in
* batches of size w. (The batch size is also known as "bucket size" and is
* equal to 1/epsilon.) Let the current batch number be b_current, starting
* with 1. For each element e we either increment its f count, if it's
* already in D, or insert a new___ triple into D with values (e, 1, b_current
* - 1). After processing each batch we prune D, by removing from it all
* elements with f + delta <= b_current. After the algorithm finishes we
* suppress all elements from D that do not satisfy f >= (s - epsilon) * N,
* where N is the total number of elements in the input. We emit the
* remaining elements with estimated frequency f/N. The LC paper proves
* that this algorithm finds all elements with true frequency at least s,
* and that no frequency is overestimated or is underestimated by more than
* epsilon. Furthermore, given reasonable assumptions about the input
* distribution, the required table size is no more than about 7 times w.
*
* In the absence of a principled basis for other particular values, we
* follow ts_typanalyze() and use parameters s = 0.07/K, epsilon = s/10.
* But we leave out the correction for stopwords, which do not apply to
* arrays. These parameters give bucket width w = K/0.007 and maximum
* expected hashtable size of about 1000 * K.
*
* Elements may repeat within an array. Since duplicates do not change the
* behavior of <@, && or @>, we want to count each element only once per
* array. Therefore, we store in the finished pg_statistic entry each
* element's frequency as the fraction of all non-null rows that contain it.
* We divide the raw counts by nonnull_cnt to get those figures.
*/
static void
compute_array_stats(VacAttrStats *stats, AnalyzeAttrFetchFunc fetchfunc,
int samplerows, double totalrows)
{
ArrayAnalyzeExtraData *extra_data;
int num_mcelem;
int null_cnt = 0;
int null_elem_cnt = 0;
int analyzed_rows = 0;
/* This is D from the LC algorithm. */
HTAB *elements_tab;
HASHCTL elem_hash_ctl;
HASH_SEQ_STATUS scan_status;
/* This is the current bucket number from the LC algorithm */
int b_current;
/* This is 'w' from the LC algorithm */
int bucket_width;
int array_no;
int64 element_no;
TrackItem *item;
int slot_idx;
HTAB *count_tab;
HASHCTL count_hash_ctl;
DECountItem *count_item;
extra_data = (ArrayAnalyzeExtraData *) stats->extra_data;
/*
* Invoke analyze.c's standard analysis function to create scalar-style
* stats for the column. It will expect its own extra_data pointer, so
* temporarily install that.
*/
stats->extra_data = extra_data->std_extra_data;
(*extra_data->std_compute_stats) (stats, fetchfunc, samplerows, totalrows);
stats->extra_data = extra_data;
/*
* Set up static pointer for use by subroutines. We wait till here in
* case std_compute_stats somehow recursively invokes us (probably not
* possible, but ...)
*/
array_extra_data = extra_data;
/*
* We want statistics_target * 10 elements in the MCELEM array. This
* multiplier is pretty arbitrary, but is meant to reflect the fact that
* the number of individual elements tracked in pg_statistic ought to be
* more than the number of values for a simple scalar column.
*/
num_mcelem = stats->attr->attstattarget * 10;
/*
* We set bucket width equal to num_mcelem / 0.007 as per the comment
* above.
*/
bucket_width = num_mcelem * 1000 / 7;
/*
* Create the hashtable. It will be in local memory, so we don't need to
* worry about overflowing the initial size. Also we don't need to pay any
* attention to locking and memory management.
*/
MemSet(&elem_hash_ctl, 0, sizeof(elem_hash_ctl));
elem_hash_ctl.keysize = sizeof(Datum);
elem_hash_ctl.entrysize = sizeof(TrackItem);
elem_hash_ctl.hash = element_hash;
elem_hash_ctl.match = element_match;
elem_hash_ctl.hcxt = CurrentMemoryContext;
elements_tab = hash_create("Analyzed elements table",
num_mcelem,
&elem_hash_ctl,
HASH_ELEM | HASH_FUNCTION | HASH_COMPARE | HASH_CONTEXT);
/* hashtable for array distinct elements counts */
MemSet(&count_hash_ctl, 0, sizeof(count_hash_ctl));
count_hash_ctl.keysize = sizeof(int);
count_hash_ctl.entrysize = sizeof(DECountItem);
count_hash_ctl.hcxt = CurrentMemoryContext;
count_tab = hash_create("Array distinct element count table",
64,
&count_hash_ctl,
HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
/* Initialize counters. */
b_current = 1;
element_no = 0;
/* Loop over the arrays. */
for (array_no = 0; array_no < samplerows; array_no++)
{
Datum value;
bool isnull;
ArrayType *array;
int num_elems;
Datum *elem_values;
bool *elem_nulls;
bool null_present;
int j;
int64 prev_element_no = element_no;
int distinct_count;
bool count_item_found;
vacuum_delay_point();
value = fetchfunc(stats, array_no, &isnull);
if (isnull)
{
/* array is null, just count that */
null_cnt++;
continue;
}
/* Skip too-large values. */
if (toast_raw_datum_size(value) > ARRAY_WIDTH_THRESHOLD)
continue;
else
analyzed_rows++;
/*
* Now detoast the array if needed, and deconstruct into datums.
*/
array = DatumGetArrayTypeP(value);
Assert(ARR_ELEMTYPE(array) == extra_data->type_id);
deconstruct_array(array,
extra_data->type_id,
extra_data->typlen,
extra_data->typbyval,
extra_data->typalign,
&elem_values, &elem_nulls, &num_elems);
/*
* We loop through the elements in the array and add them to our
* tracking hashtable.
*/
null_present = false;
for (j = 0; j < num_elems; j++)
{
Datum elem_value;
bool found;
/* No null element processing other than flag setting here */
if (elem_nulls[j])
{
null_present = true;
continue;
}
/* Lookup current element in hashtable, adding it if new___ */
elem_value = elem_values[j];
item = (TrackItem *) hash_search(elements_tab,
(const void *) &elem_value,
HASH_ENTER, &found);
if (found)
{
/* The element value is already on the tracking list */
/*
* The operators we assist ignore duplicate array elements, so
* count a given distinct element only once per array.
*/
if (item->last_container == array_no)
continue;
item->frequency++;
item->last_container = array_no;
}
else
{
/* Initialize new___ tracking list element */
/*
* If element type is pass-by-reference, we must copy it into
* palloc'd space, so that we can release the array below. (We
* do this so that the space needed for element values is
* limited by the size of the hashtable; if we kept all the
* array values around, it could be much more.)
*/
item->key = datumCopy(elem_value,
extra_data->typbyval,
extra_data->typlen);
item->frequency = 1;
item->delta = b_current - 1;
item->last_container = array_no;
}
/* element_no is the number of elements processed (ie N) */
element_no++;
/* We prune the D structure after processing each bucket */
if (element_no % bucket_width == 0)
{
prune_element_hashtable(elements_tab, b_current);
b_current++;
}
}
/* Count null element presence once per array. */
if (null_present)
null_elem_cnt++;
/* Update frequency of the particular array distinct element count. */
distinct_count = (int) (element_no - prev_element_no);
count_item = (DECountItem *) hash_search(count_tab, &distinct_count,
HASH_ENTER,
&count_item_found);
if (count_item_found)
count_item->frequency++;
else
count_item->frequency = 1;
/* Free memory allocated while detoasting. */
if (PointerGetDatum(array) != value)
pfree(array);
pfree(elem_values);
pfree(elem_nulls);
}
/* Skip pg_statistic slots occupied by standard statistics */
slot_idx = 0;
while (slot_idx < STATISTIC_NUM_SLOTS && stats->stakind[slot_idx] != 0)
slot_idx++;
if (slot_idx > STATISTIC_NUM_SLOTS - 2)
elog(ERROR, "insufficient pg_statistic slots for array stats");
/* We can only compute real stats if we found some non-null values. */
if (analyzed_rows > 0)
{
int nonnull_cnt = analyzed_rows;
int count_items_count;
int i;
TrackItem **sort_table;
int track_len;
int64 cutoff_freq;
int64 minfreq,
maxfreq;
/*
* We assume the standard stats code already took care of setting
* stats_valid, stanullfrac, stawidth, stadistinct. We'd have to
* re-compute those values if we wanted to not store the standard
* stats.
*/
/*
* Construct an array of the interesting hashtable items, that is,
* those meeting the cutoff frequency (s - epsilon)*N. Also identify
* the minimum and maximum frequencies among these items.
*
* Since epsilon = s/10 and bucket_width = 1/epsilon, the cutoff
* frequency is 9*N / bucket_width.
*/
cutoff_freq = 9 * element_no / bucket_width;
i = hash_get_num_entries(elements_tab); /* surely enough space */
sort_table = (TrackItem **) palloc(sizeof(TrackItem *) * i);
hash_seq_init(&scan_status, elements_tab);
track_len = 0;
minfreq = element_no;
maxfreq = 0;
while ((item = (TrackItem *) hash_seq_search(&scan_status)) != NULL)
{
if (item->frequency > cutoff_freq)
{
sort_table[track_len++] = item;
minfreq = Min(minfreq, item->frequency);
maxfreq = Max(maxfreq, item->frequency);
}
}
Assert(track_len <= i);
/* emit some statistics for debug purposes */
elog(DEBUG3, "compute_array_stats: target # mces = %d, "
"bucket width = %d, "
"# elements = " INT64_FORMAT ", hashtable size = %d, "
"usable entries = %d",
num_mcelem, bucket_width, element_no, i, track_len);
/*
* If we obtained more elements than we really want, get rid of those
* with least frequencies. The easiest way is to qsort the array into
* descending frequency order and truncate the array.
*/
if (num_mcelem < track_len)
{
qsort(sort_table, track_len, sizeof(TrackItem *),
trackitem_compare_frequencies_desc);
/* reset minfreq to the smallest frequency we're keeping */
minfreq = sort_table[num_mcelem - 1]->frequency;
}
else
num_mcelem = track_len;
/* Generate MCELEM slot entry */
if (num_mcelem > 0)
{
MemoryContext old_context;
Datum *mcelem_values;
float4 *mcelem_freqs;
/*
* We want to store statistics sorted on the element value using
* the element type's default comparison function. This permits
* fast binary searches in selectivity estimation functions.
*/
qsort(sort_table, num_mcelem, sizeof(TrackItem *),
trackitem_compare_element);
/* Must copy the target values into anl_context */
old_context = MemoryContextSwitchTo(stats->anl_context);
/*
* We sorted statistics on the element value, but we want to be
* able to find the minimal and maximal frequencies without going
* through all the values. We also want the frequency of null
* elements. Store these three values at the end of mcelem_freqs.
*/
mcelem_values = (Datum *) palloc(num_mcelem * sizeof(Datum));
mcelem_freqs = (float4 *) palloc((num_mcelem + 3) * sizeof(float4));
/*
* See comments above about use of nonnull_cnt as the divisor for
* the final frequency estimates.
*/
for (i = 0; i < num_mcelem; i++)
{
TrackItem *item = sort_table[i];
mcelem_values[i] = datumCopy(item->key,
extra_data->typbyval,
extra_data->typlen);
mcelem_freqs[i] = (double) item->frequency /
(double) nonnull_cnt;
}
mcelem_freqs[i++] = (double) minfreq / (double) nonnull_cnt;
mcelem_freqs[i++] = (double) maxfreq / (double) nonnull_cnt;
mcelem_freqs[i++] = (double) null_elem_cnt / (double) nonnull_cnt;
MemoryContextSwitchTo(old_context);
stats->stakind[slot_idx] = STATISTIC_KIND_MCELEM;
stats->staop[slot_idx] = extra_data->eq_opr;
stats->stanumbers[slot_idx] = mcelem_freqs;
/* See above comment about extra stanumber entries */
stats->numnumbers[slot_idx] = num_mcelem + 3;
stats->stavalues[slot_idx] = mcelem_values;
stats->numvalues[slot_idx] = num_mcelem;
/* We are storing values of element type */
stats->statypid[slot_idx] = extra_data->type_id;
stats->statyplen[slot_idx] = extra_data->typlen;
stats->statypbyval[slot_idx] = extra_data->typbyval;
stats->statypalign[slot_idx] = extra_data->typalign;
slot_idx++;
}
/* Generate DECHIST slot entry */
count_items_count = hash_get_num_entries(count_tab);
if (count_items_count > 0)
{
int num_hist = stats->attr->attstattarget;
DECountItem **sorted_count_items;
int j;
int delta;
int64 frac;
float4 *hist;
/* num_hist must be at least 2 for the loop below to work */
num_hist = Max(num_hist, 2);
/*
* Create an array of DECountItem pointers, and sort them into
* increasing count order.
*/
sorted_count_items = (DECountItem **)
palloc(sizeof(DECountItem *) * count_items_count);
hash_seq_init(&scan_status, count_tab);
j = 0;
while ((count_item = (DECountItem *) hash_seq_search(&scan_status)) != NULL)
{
sorted_count_items[j++] = count_item;
}
qsort(sorted_count_items, count_items_count,
sizeof(DECountItem *), countitem_compare_count);
/*
* Prepare to fill stanumbers with the histogram, followed by the
* average count. This array must be stored in anl_context.
*/
hist = (float4 *)
MemoryContextAlloc(stats->anl_context,
sizeof(float4) * (num_hist + 1));
hist[num_hist] = (double) element_no / (double) nonnull_cnt;
/*----------
* Construct the histogram of distinct-element counts (DECs).
*
* The object of this loop is to copy the min and max DECs to
* hist[0] and hist[num_hist - 1], along with evenly-spaced DECs
* in between (where "evenly-spaced" is with reference to the
* whole input population of arrays). If we had a complete sorted
* array of DECs, one per analyzed row, the i'th hist value would
* come from DECs[i * (analyzed_rows - 1) / (num_hist - 1)]
* (compare the histogram-making loop in compute_scalar_stats()).
* But instead of that we have the sorted_count_items[] array,
* which holds unique DEC values with their frequencies (that is,
* a run-length-compressed version of the full array). So we
* control advancing through sorted_count_items[] with the
* variable "frac", which is defined as (x - y) * (num_hist - 1),
* where x is the index in the notional DECs array corresponding
* to the start of the next sorted_count_items[] element's run,
* and y is the index in DECs from which we should take the next
* histogram value. We have to advance whenever x <= y, that is
* frac <= 0. The x component is the sum of the frequencies seen
* so far (up through the current sorted_count_items[] element),
* and of course y * (num_hist - 1) = i * (analyzed_rows - 1),
* per the subscript calculation above. (The subscript calculation
* implies dropping any fractional part of y; in this formulation
* that's handled by not advancing until frac reaches 1.)
*
* Even though frac has a bounded range, it could overflow int32
* when working with very large statistics targets, so we do that
* math in int64.
*----------
*/
delta = analyzed_rows - 1;
j = 0; /* current index in sorted_count_items */
/* Initialize frac for sorted_count_items[0]; y is initially 0 */
frac = (int64) sorted_count_items[0]->frequency * (num_hist - 1);
for (i = 0; i < num_hist; i++)
{
while (frac <= 0)
{
/* Advance, and update x component of frac */
j++;
frac += (int64) sorted_count_items[j]->frequency * (num_hist - 1);
}
hist[i] = sorted_count_items[j]->count;
frac -= delta; /* update y for upcoming i increment */
}
Assert(j == count_items_count - 1);
stats->stakind[slot_idx] = STATISTIC_KIND_DECHIST;
stats->staop[slot_idx] = extra_data->eq_opr;
stats->stanumbers[slot_idx] = hist;
stats->numnumbers[slot_idx] = num_hist + 1;
slot_idx++;
}
}
/*
* We don't need to bother cleaning up any of our temporary palloc's. The
* hashtable should also go away, as it used a child memory context.
*/
}
/*
* Convert a BrinTuple back to a BrinMemTuple. This is the reverse of
* brin_form_tuple.
*
* As an optimization, the caller can pass a previously allocated 'dMemtuple'.
* This avoids having to allocate it here, which can be useful when this
* function is called many times in a loop. It is caller's responsibility
* that the given BrinMemTuple matches what we need here.
*
* Note we don't need the "on disk tupdesc" here; we rely on our own routine to
* deconstruct the tuple from the on-disk format.
*/
BrinMemTuple *
brin_deform_tuple(BrinDesc *brdesc, BrinTuple *tuple, BrinMemTuple *dMemtuple)
{
BrinMemTuple *dtup;
Datum *values;
bool *allnulls;
bool *hasnulls;
char *tp;
bits8 *nullbits;
int keyno;
int valueno;
MemoryContext oldcxt;
dtup = dMemtuple ? brin_memtuple_initialize(dMemtuple, brdesc) :
brin_new_memtuple(brdesc);
if (BrinTupleIsPlaceholder(tuple))
dtup->bt_placeholder = true;
dtup->bt_blkno = tuple->bt_blkno;
values = dtup->bt_values;
allnulls = dtup->bt_allnulls;
hasnulls = dtup->bt_hasnulls;
tp = (char *) tuple + BrinTupleDataOffset(tuple);
if (BrinTupleHasNulls(tuple))
nullbits = (bits8 *) ((char *) tuple + SizeOfBrinTuple);
else
nullbits = NULL;
brin_deconstruct_tuple(brdesc,
tp, nullbits, BrinTupleHasNulls(tuple),
values, allnulls, hasnulls);
/*
* Iterate to assign each of the values to the corresponding item in the
* values array of each column. The copies occur in the tuple's context.
*/
oldcxt = MemoryContextSwitchTo(dtup->bt_context);
for (valueno = 0, keyno = 0; keyno < brdesc->bd_tupdesc->natts; keyno++)
{
int i;
if (allnulls[keyno])
{
valueno += brdesc->bd_info[keyno]->oi_nstored;
continue;
}
/*
* We would like to skip datumCopy'ing the values datum in some cases,
* caller permitting ...
*/
for (i = 0; i < brdesc->bd_info[keyno]->oi_nstored; i++)
dtup->bt_columns[keyno].bv_values[i] =
datumCopy(values[valueno++],
brdesc->bd_info[keyno]->oi_typcache[i]->typbyval,
brdesc->bd_info[keyno]->oi_typcache[i]->typlen);
dtup->bt_columns[keyno].bv_hasnulls = hasnulls[keyno];
dtup->bt_columns[keyno].bv_allnulls = false;
}
MemoryContextSwitchTo(oldcxt);
return dtup;
}
/*
* Copied from Postgres' src/backend/optimizer/util/clauses.c
*
* evaluate_expr: pre-evaluate a constant expression
*
* We use the executor's routine ExecEvalExpr() to avoid duplication of
* code and ensure we get the same result as the executor would get.
*/
Expr *
evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
Oid result_collation)
{
EState *estate;
ExprState *exprstate;
MemoryContext oldcontext;
Datum const_val;
bool const_is_null;
int16 resultTypLen;
bool resultTypByVal;
/*
* To use the executor, we need an EState.
*/
estate = CreateExecutorState();
/* We can use the estate's working context to avoid memory leaks. */
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
/* Make sure any opfuncids are filled in. */
fix_opfuncids((Node *) expr);
/*
* Prepare expr for execution. (Note: we can't use ExecPrepareExpr
* because it'd result in recursively invoking eval_const_expressions.)
*/
exprstate = ExecInitExpr(expr, NULL);
/*
* And evaluate it.
*
* It is OK to use a default econtext because none of the ExecEvalExpr()
* code used in this situation will use econtext. That might seem
* fortuitous, but it's not so unreasonable --- a constant expression does
* not depend on context, by definition, n'est ce pas?
*/
const_val = ExecEvalExprSwitchContext(exprstate,
GetPerTupleExprContext(estate),
&const_is_null, NULL);
/* Get info needed about result datatype */
get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
/* Get back to outer memory context */
MemoryContextSwitchTo(oldcontext);
/*
* Must copy result out of sub-context used by expression eval.
*
* Also, if it's varlena, forcibly detoast it. This protects us against
* storing TOAST pointers into plans that might outlive the referenced
* data. (makeConst would handle detoasting anyway, but it's worth a few
* extra lines here so that we can do the copy and detoast in one step.)
*/
if (!const_is_null)
{
if (resultTypLen == -1)
const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
else
const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
}
/* Release all the junk we just created */
FreeExecutorState(estate);
/*
* Make the constant result node.
*/
return (Expr *) makeConst(result_type, result_typmod, result_collation,
resultTypLen,
const_val, const_is_null,
resultTypByVal);
}
