/*
* Receive a tuple from the executor and store it in the tuplestore.
* This is for the case where we have to detoast any toasted values.
*/
static void
tstoreReceiveSlot_detoast(TupleTableSlot *slot, DestReceiver *self)
{
TStoreState *myState = (TStoreState *) self;
TupleDesc typeinfo = slot->tts_tupleDescriptor;
Form_pg_attribute *attrs = typeinfo->attrs;
int natts = typeinfo->natts;
int nfree;
int i;
HeapTuple tuple;
MemoryContext oldcxt;
/* Make sure the tuple is fully deconstructed */
slot_getallattrs(slot);
/*
* Fetch back any out-of-line datums. We build the new datums array in
* myState->outvalues[] (but we can re-use the slot's isnull array).
* Also, remember the fetched values to free afterwards.
*/
nfree = 0;
for (i = 0; i < natts; i++)
{
Datum val = slot->tts_values[i];
if (!attrs[i]->attisdropped &&
attrs[i]->attlen == -1 &&
!slot->tts_isnull[i])
{
if (VARATT_IS_EXTERNAL(DatumGetPointer(val)))
{
val = PointerGetDatum(heap_tuple_fetch_attr((varattrib *)
DatumGetPointer(val)));
myState->tofree[nfree++] = val;
}
}
myState->outvalues[i] = val;
}
/*
* Push the modified tuple into the tuplestore.
*/
tuple = heap_form_tuple(typeinfo,
myState->outvalues, slot->tts_isnull);
oldcxt = MemoryContextSwitchTo(myState->cxt);
tuplestore_puttuple(myState->tstore, tuple);
MemoryContextSwitchTo(oldcxt);
heap_freetuple(tuple);
/* And release any temporary detoasted values */
for (i = 0; i < nfree; i++)
pfree(DatumGetPointer(myState->tofree[i]));
}
/* ----------
* toast_insert_or_update -
*
* Delete no-longer-used toast-entries and create new ones to
* make the new tuple fit on INSERT or UPDATE
*
* Inputs:
* newtup: the candidate new tuple to be inserted
* oldtup: the old row version for UPDATE, or NULL for INSERT
* options: options to be passed to heap_insert() for toast rows
* Result:
* either newtup if no toasting is needed, or a palloc'd modified tuple
* that is what should actually get stored
*
* NOTE: neither newtup nor oldtup will be modified. This is a change
* from the pre-8.1 API of this routine.
* ----------
*/
HeapTuple
toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup,
int options)
{
HeapTuple result_tuple;
TupleDesc tupleDesc;
Form_pg_attribute *att;
int numAttrs;
int i;
bool need_change = false;
bool need_free = false;
bool need_delold = false;
bool has_nulls = false;
Size maxDataLen;
Size hoff;
char toast_action[MaxHeapAttributeNumber];
bool toast_isnull[MaxHeapAttributeNumber];
bool toast_oldisnull[MaxHeapAttributeNumber];
Datum toast_values[MaxHeapAttributeNumber];
Datum toast_oldvalues[MaxHeapAttributeNumber];
int32 toast_sizes[MaxHeapAttributeNumber];
bool toast_free[MaxHeapAttributeNumber];
bool toast_delold[MaxHeapAttributeNumber];
/*
* We should only ever be called for tuples of plain relations ---
* recursing on a toast rel is bad news.
*/
Assert(rel->rd_rel->relkind == RELKIND_RELATION);
/*
* Get the tuple descriptor and break down the tuple(s) into fields.
*/
tupleDesc = rel->rd_att;
att = tupleDesc->attrs;
numAttrs = tupleDesc->natts;
Assert(numAttrs <= MaxHeapAttributeNumber);
heap_deform_tuple(newtup, tupleDesc, toast_values, toast_isnull);
if (oldtup != NULL)
heap_deform_tuple(oldtup, tupleDesc, toast_oldvalues, toast_oldisnull);
/* ----------
* Then collect information about the values given
*
* NOTE: toast_action[i] can have these values:
* ' ' default handling
* 'p' already processed --- don't touch it
* 'x' incompressible, but OK to move off
*
* NOTE: toast_sizes[i] is only made valid for varlena attributes with
* toast_action[i] different from 'p'.
* ----------
*/
memset(toast_action, ' ', numAttrs * sizeof(char));
memset(toast_free, 0, numAttrs * sizeof(bool));
memset(toast_delold, 0, numAttrs * sizeof(bool));
for (i = 0; i < numAttrs; i++)
{
struct varlena *old_value;
struct varlena *new_value;
if (oldtup != NULL)
{
/*
* For UPDATE get the old and new values of this attribute
*/
old_value = (struct varlena *) DatumGetPointer(toast_oldvalues[i]);
new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
/*
* If the old value is an external stored one, check if it has
* changed so we have to delete it later.
*/
if (att[i]->attlen == -1 && !toast_oldisnull[i] &&
VARATT_IS_EXTERNAL(old_value))
{
if (toast_isnull[i] || !VARATT_IS_EXTERNAL(new_value) ||
memcmp((char *) old_value, (char *) new_value,
VARSIZE_EXTERNAL(old_value)) != 0)
{
/*
* The old external stored value isn't needed any more
* after the update
*/
toast_delold[i] = true;
need_delold = true;
}
else
{
/*
* This attribute isn't changed by this update so we reuse
* the original reference to the old value in the new
* tuple.
*/
toast_action[i] = 'p';
continue;
}
}
}
else
{
/*
* For INSERT simply get the new value
*/
new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
}
/*
* Handle NULL attributes
*/
if (toast_isnull[i])
{
toast_action[i] = 'p';
has_nulls = true;
continue;
}
/*
* Now look at varlena attributes
*/
if (att[i]->attlen == -1)
{
/*
* If the table's attribute says PLAIN always, force it so.
*/
if (att[i]->attstorage == 'p')
toast_action[i] = 'p';
/*
* We took care of UPDATE above, so any external value we find
* still in the tuple must be someone else's we cannot reuse.
* Fetch it back (without decompression, unless we are forcing
* PLAIN storage). If necessary, we'll push it out as a new
* external value below.
*/
if (VARATT_IS_EXTERNAL(new_value))
{
if (att[i]->attstorage == 'p')
new_value = heap_tuple_untoast_attr(new_value);
else
new_value = heap_tuple_fetch_attr(new_value);
toast_values[i] = PointerGetDatum(new_value);
toast_free[i] = true;
need_change = true;
need_free = true;
}
/*
* Remember the size of this attribute
*/
toast_sizes[i] = VARSIZE_ANY(new_value);
}
else
{
/*
* Not a varlena attribute, plain storage always
*/
toast_action[i] = 'p';
}
}
/* ----------
* Compress and/or save external until data fits into target length
*
* 1: Inline compress attributes with attstorage 'x', and store very
* large attributes with attstorage 'x' or 'e' external immediately
* 2: Store attributes with attstorage 'x' or 'e' external
* 3: Inline compress attributes with attstorage 'm'
* 4: Store attributes with attstorage 'm' external
* ----------
*/
/* compute header overhead --- this should match heap_form_tuple() */
hoff = offsetof(HeapTupleHeaderData, t_bits);
if (has_nulls)
hoff += BITMAPLEN(numAttrs);
if (newtup->t_data->t_infomask & HEAP_HASOID)
hoff += sizeof(Oid);
hoff = MAXALIGN(hoff);
Assert(hoff == newtup->t_data->t_hoff);
/* now convert to a limit on the tuple data size */
maxDataLen = TOAST_TUPLE_TARGET - hoff;
/*
* Look for attributes with attstorage 'x' to compress. Also find large
* attributes with attstorage 'x' or 'e', and store them external.
*/
while (heap_compute_data_size(tupleDesc,
toast_values, toast_isnull) > maxDataLen)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
Datum old_value;
Datum new_value;
/*
* Search for the biggest yet unprocessed internal attribute
*/
for (i = 0; i < numAttrs; i++)
{
if (toast_action[i] != ' ')
continue;
if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
continue; /* can't happen, toast_action would be 'p' */
if (VARATT_IS_COMPRESSED(DatumGetPointer(toast_values[i])))
continue;
if (att[i]->attstorage != 'x' && att[i]->attstorage != 'e')
continue;
if (toast_sizes[i] > biggest_size)
{
biggest_attno = i;
biggest_size = toast_sizes[i];
}
}
if (biggest_attno < 0)
break;
/*
* Attempt to compress it inline, if it has attstorage 'x'
*/
i = biggest_attno;
if (att[i]->attstorage == 'x')
{
old_value = toast_values[i];
new_value = toast_compress_datum(old_value);
if (DatumGetPointer(new_value) != NULL)
{
/* successful compression */
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_values[i] = new_value;
toast_free[i] = true;
toast_sizes[i] = VARSIZE(DatumGetPointer(toast_values[i]));
need_change = true;
need_free = true;
}
else
{
/* incompressible, ignore on subsequent compression passes */
toast_action[i] = 'x';
}
}
else
{
/* has attstorage 'e', ignore on subsequent compression passes */
toast_action[i] = 'x';
}
/*
* If this value is by itself more than maxDataLen (after compression
* if any), push it out to the toast table immediately, if possible.
* This avoids uselessly compressing other fields in the common case
* where we have one long field and several short ones.
*
* XXX maybe the threshold should be less than maxDataLen?
*/
if (toast_sizes[i] > maxDataLen &&
rel->rd_rel->reltoastrelid != InvalidOid)
{
old_value = toast_values[i];
toast_action[i] = 'p';
toast_values[i] = toast_save_datum(rel, toast_values[i], options);
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_free[i] = true;
need_change = true;
need_free = true;
}
}
/*
* Second we look for attributes of attstorage 'x' or 'e' that are still
* inline. But skip this if there's no toast table to push them to.
*/
while (heap_compute_data_size(tupleDesc,
toast_values, toast_isnull) > maxDataLen &&
rel->rd_rel->reltoastrelid != InvalidOid)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
Datum old_value;
/*------
* Search for the biggest yet inlined attribute with
* attstorage equals 'x' or 'e'
*------
*/
for (i = 0; i < numAttrs; i++)
{
if (toast_action[i] == 'p')
continue;
if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
continue; /* can't happen, toast_action would be 'p' */
if (att[i]->attstorage != 'x' && att[i]->attstorage != 'e')
continue;
if (toast_sizes[i] > biggest_size)
{
biggest_attno = i;
biggest_size = toast_sizes[i];
}
}
if (biggest_attno < 0)
break;
/*
* Store this external
*/
i = biggest_attno;
old_value = toast_values[i];
toast_action[i] = 'p';
toast_values[i] = toast_save_datum(rel, toast_values[i], options);
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_free[i] = true;
need_change = true;
need_free = true;
}
/*
* Round 3 - this time we take attributes with storage 'm' into
* compression
*/
while (heap_compute_data_size(tupleDesc,
toast_values, toast_isnull) > maxDataLen)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
Datum old_value;
Datum new_value;
/*
* Search for the biggest yet uncompressed internal attribute
*/
for (i = 0; i < numAttrs; i++)
{
if (toast_action[i] != ' ')
continue;
if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
continue; /* can't happen, toast_action would be 'p' */
if (VARATT_IS_COMPRESSED(DatumGetPointer(toast_values[i])))
continue;
if (att[i]->attstorage != 'm')
continue;
if (toast_sizes[i] > biggest_size)
{
biggest_attno = i;
biggest_size = toast_sizes[i];
}
}
if (biggest_attno < 0)
break;
/*
* Attempt to compress it inline
*/
i = biggest_attno;
old_value = toast_values[i];
new_value = toast_compress_datum(old_value);
if (DatumGetPointer(new_value) != NULL)
{
/* successful compression */
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_values[i] = new_value;
toast_free[i] = true;
toast_sizes[i] = VARSIZE(DatumGetPointer(toast_values[i]));
need_change = true;
need_free = true;
}
else
{
/* incompressible, ignore on subsequent compression passes */
toast_action[i] = 'x';
}
}
/*
* Finally we store attributes of type 'm' externally. At this point we
* increase the target tuple size, so that 'm' attributes aren't stored
* externally unless really necessary.
*/
maxDataLen = TOAST_TUPLE_TARGET_MAIN - hoff;
while (heap_compute_data_size(tupleDesc,
toast_values, toast_isnull) > maxDataLen &&
rel->rd_rel->reltoastrelid != InvalidOid)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
Datum old_value;
/*--------
* Search for the biggest yet inlined attribute with
* attstorage = 'm'
*--------
*/
for (i = 0; i < numAttrs; i++)
{
if (toast_action[i] == 'p')
continue;
if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
continue; /* can't happen, toast_action would be 'p' */
if (att[i]->attstorage != 'm')
continue;
if (toast_sizes[i] > biggest_size)
{
biggest_attno = i;
biggest_size = toast_sizes[i];
}
}
if (biggest_attno < 0)
break;
/*
* Store this external
*/
i = biggest_attno;
old_value = toast_values[i];
toast_action[i] = 'p';
toast_values[i] = toast_save_datum(rel, toast_values[i], options);
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_free[i] = true;
need_change = true;
need_free = true;
}
/*
* In the case we toasted any values, we need to build a new heap tuple
* with the changed values.
*/
if (need_change)
{
HeapTupleHeader olddata = newtup->t_data;
HeapTupleHeader new_data;
int32 new_len;
int32 new_data_len;
/*
* Calculate the new size of the tuple. Header size should not
* change, but data size might.
*/
new_len = offsetof(HeapTupleHeaderData, t_bits);
if (has_nulls)
new_len += BITMAPLEN(numAttrs);
if (olddata->t_infomask & HEAP_HASOID)
new_len += sizeof(Oid);
new_len = MAXALIGN(new_len);
Assert(new_len == olddata->t_hoff);
new_data_len = heap_compute_data_size(tupleDesc,
toast_values, toast_isnull);
new_len += new_data_len;
/*
* Allocate and zero the space needed, and fill HeapTupleData fields.
*/
result_tuple = (HeapTuple) palloc0(HEAPTUPLESIZE + new_len);
result_tuple->t_len = new_len;
result_tuple->t_self = newtup->t_self;
result_tuple->t_tableOid = newtup->t_tableOid;
new_data = (HeapTupleHeader) ((char *) result_tuple + HEAPTUPLESIZE);
result_tuple->t_data = new_data;
/*
* Put the existing tuple header and the changed values into place
*/
memcpy(new_data, olddata, olddata->t_hoff);
heap_fill_tuple(tupleDesc,
toast_values,
toast_isnull,
(char *) new_data + olddata->t_hoff,
new_data_len,
&(new_data->t_infomask),
has_nulls ? new_data->t_bits : NULL);
}
else
result_tuple = newtup;
/*
* Free allocated temp values
*/
if (need_free)
for (i = 0; i < numAttrs; i++)
if (toast_free[i])
pfree(DatumGetPointer(toast_values[i]));
/*
* Delete external values from the old tuple
*/
if (need_delold)
for (i = 0; i < numAttrs; i++)
if (toast_delold[i])
toast_delete_datum(rel, toast_oldvalues[i]);
return result_tuple;
}
/* ----------------
* index_form_tuple
*
* This shouldn't leak any memory; otherwise, callers such as
* tuplesort_putindextuplevalues() will be very unhappy.
* ----------------
*/
IndexTuple
index_form_tuple(TupleDesc tupleDescriptor,
Datum *values,
bool *isnull)
{
char *tp; /* tuple pointer */
IndexTuple tuple; /* return tuple */
Size size,
data_size,
hoff;
int i;
unsigned short infomask = 0;
bool hasnull = false;
uint16 tupmask = 0;
int numberOfAttributes = tupleDescriptor->natts;
#ifdef TOAST_INDEX_HACK
Datum untoasted_values[INDEX_MAX_KEYS];
bool untoasted_free[INDEX_MAX_KEYS];
#endif
if (numberOfAttributes > INDEX_MAX_KEYS)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("number of index columns (%d) exceeds limit (%d)",
numberOfAttributes, INDEX_MAX_KEYS)));
#ifdef TOAST_INDEX_HACK
for (i = 0; i < numberOfAttributes; i++)
{
Form_pg_attribute att = tupleDescriptor->attrs[i];
untoasted_values[i] = values[i];
untoasted_free[i] = false;
/* Do nothing if value is NULL or not of varlena type */
if (isnull[i] || att->attlen != -1)
continue;
/*
* If value is stored EXTERNAL, must fetch it so we are not depending
* on outside storage. This should be improved someday.
*/
if (VARATT_IS_EXTERNAL(DatumGetPointer(values[i])))
{
untoasted_values[i] =
PointerGetDatum(heap_tuple_fetch_attr((struct varlena *)
DatumGetPointer(values[i])));
untoasted_free[i] = true;
}
/*
* If value is above size target, and is of a compressible datatype,
* try to compress it in-line.
*/
if (!VARATT_IS_EXTENDED(DatumGetPointer(untoasted_values[i])) &&
VARSIZE(DatumGetPointer(untoasted_values[i])) > TOAST_INDEX_TARGET &&
(att->attstorage == 'x' || att->attstorage == 'm'))
{
Datum cvalue = toast_compress_datum(untoasted_values[i]);
if (DatumGetPointer(cvalue) != NULL)
{
/* successful compression */
if (untoasted_free[i])
pfree(DatumGetPointer(untoasted_values[i]));
untoasted_values[i] = cvalue;
untoasted_free[i] = true;
}
}
}
#endif
for (i = 0; i < numberOfAttributes; i++)
{
if (isnull[i])
{
hasnull = true;
break;
}
}
if (hasnull)
infomask |= INDEX_NULL_MASK;
hoff = IndexInfoFindDataOffset(infomask);
#ifdef TOAST_INDEX_HACK
data_size = heap_compute_data_size(tupleDescriptor,
untoasted_values, isnull);
#else
data_size = heap_compute_data_size(tupleDescriptor,
values, isnull);
#endif
size = hoff + data_size;
size = MAXALIGN(size); /* be conservative */
tp = (char *) palloc0(size);
tuple = (IndexTuple) tp;
heap_fill_tuple(tupleDescriptor,
#ifdef TOAST_INDEX_HACK
untoasted_values,
#else
values,
#endif
isnull,
(char *) tp + hoff,
data_size,
&tupmask,
(hasnull ? (bits8 *) tp + sizeof(IndexTupleData) : NULL));
#ifdef TOAST_INDEX_HACK
for (i = 0; i < numberOfAttributes; i++)
{
if (untoasted_free[i])
pfree(DatumGetPointer(untoasted_values[i]));
}
#endif
/*
* We do this because heap_fill_tuple wants to initialize a "tupmask"
* which is used for HeapTuples, but we want an indextuple infomask. The
* only relevant info is the "has variable attributes" field. We have
* already set the hasnull bit above.
*/
if (tupmask & HEAP_HASVARWIDTH)
infomask |= INDEX_VAR_MASK;
/* Also assert we got rid of external attributes */
#ifdef TOAST_INDEX_HACK
Assert((tupmask & HEAP_HASEXTERNAL) == 0);
#endif
/*
* Here we make sure that the size will fit in the field reserved for it
* in t_info.
*/
if ((size & INDEX_SIZE_MASK) != size)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("index row requires %zu bytes, maximum size is %zu",
size, (Size) INDEX_SIZE_MASK)));
infomask |= size;
/*
* initialize metadata
*/
tuple->t_info = infomask;
return tuple;
}
Datum
make_tuple_indirect(PG_FUNCTION_ARGS)
{
HeapTupleHeader rec = PG_GETARG_HEAPTUPLEHEADER(0);
HeapTupleData tuple;
int ncolumns;
Datum *values;
bool *nulls;
Oid tupType;
int32 tupTypmod;
TupleDesc tupdesc;
HeapTuple newtup;
int i;
MemoryContext old_context;
/* Extract type info from the tuple itself */
tupType = HeapTupleHeaderGetTypeId(rec);
tupTypmod = HeapTupleHeaderGetTypMod(rec);
tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
ncolumns = tupdesc->natts;
/* Build a temporary HeapTuple control structure */
tuple.t_len = HeapTupleHeaderGetDatumLength(rec);
ItemPointerSetInvalid(&(tuple.t_self));
tuple.t_tableOid = InvalidOid;
tuple.t_data = rec;
values = (Datum *) palloc(ncolumns * sizeof(Datum));
nulls = (bool *) palloc(ncolumns * sizeof(bool));
heap_deform_tuple(&tuple, tupdesc, values, nulls);
old_context = MemoryContextSwitchTo(TopTransactionContext);
for (i = 0; i < ncolumns; i++)
{
struct varlena *attr;
struct varlena *new_attr;
struct varatt_indirect redirect_pointer;
/* only work on existing, not-null varlenas */
if (TupleDescAttr(tupdesc, i)->attisdropped ||
nulls[i] ||
TupleDescAttr(tupdesc, i)->attlen != -1)
continue;
attr = (struct varlena *) DatumGetPointer(values[i]);
/* don't recursively indirect */
if (VARATT_IS_EXTERNAL_INDIRECT(attr))
continue;
/* copy datum, so it still lives later */
if (VARATT_IS_EXTERNAL_ONDISK(attr))
attr = heap_tuple_fetch_attr(attr);
else
{
struct varlena *oldattr = attr;
attr = palloc0(VARSIZE_ANY(oldattr));
memcpy(attr, oldattr, VARSIZE_ANY(oldattr));
}
/* build indirection Datum */
new_attr = (struct varlena *) palloc0(INDIRECT_POINTER_SIZE);
redirect_pointer.pointer = attr;
SET_VARTAG_EXTERNAL(new_attr, VARTAG_INDIRECT);
memcpy(VARDATA_EXTERNAL(new_attr), &redirect_pointer,
sizeof(redirect_pointer));
values[i] = PointerGetDatum(new_attr);
}
newtup = heap_form_tuple(tupdesc, values, nulls);
pfree(values);
pfree(nulls);
ReleaseTupleDesc(tupdesc);
MemoryContextSwitchTo(old_context);
/*
* We intentionally don't use PG_RETURN_HEAPTUPLEHEADER here, because that
* would cause the indirect toast pointers to be flattened out of the
* tuple immediately, rendering subsequent testing irrelevant. So just
* return the HeapTupleHeader pointer as-is. This violates the general
* rule that composite Datums shouldn't contain toast pointers, but so
* long as the regression test scripts don't insert the result of this
* function into a container type (record, array, etc) it should be OK.
*/
PG_RETURN_POINTER(newtup->t_data);
}
int64
datumstreamwrite_lob(DatumStreamWrite * acc,
Datum d,
AppendOnlyBlockDirectory *blockDirectory,
int colGroupNo,
bool addColAction)
{
uint8 *p;
int32 varLen;
Assert(acc);
Assert(acc->datumStreamVersion == DatumStreamVersion_Original ||
acc->datumStreamVersion == DatumStreamVersion_Dense ||
acc->datumStreamVersion == DatumStreamVersion_Dense_Enhanced);
if (acc->typeInfo.datumlen >= 0)
{
elog(ERROR, "Large object must be variable length objects (varlena)");
}
/*
* If the datum is toasted / compressed -- an error.
*/
if (VARATT_IS_EXTENDED(DatumGetPointer(d)))
{
elog(ERROR, "Expected large object / variable length objects (varlena) to be de-toasted and/or de-compressed at this point");
}
/*
* De-Toast Datum
*/
if (VARATT_IS_EXTERNAL(DatumGetPointer(d)))
{
d = PointerGetDatum(heap_tuple_fetch_attr(DatumGetPointer(d)));
}
p = (uint8 *) DatumGetPointer(d);
varLen = VARSIZE_ANY(p);
if (Debug_datumstream_write_print_large_varlena_info)
{
datumstreamwrite_print_large_varlena_info(
acc,
p);
}
/* Set the BlockFirstRowNum */
AppendOnlyStorageWrite_SetFirstRowNum(&acc->ao_write,
acc->blockFirstRowNum);
AppendOnlyStorageWrite_Content(
&acc->ao_write,
p,
varLen,
AOCSBK_BLOB,
/* rowCount */ 1);
/* Insert an entry to the block directory */
AppendOnlyBlockDirectory_InsertEntry(
blockDirectory,
colGroupNo,
acc->blockFirstRowNum,
AppendOnlyStorageWrite_LogicalBlockStartOffset(&acc->ao_write),
1, /*itemCount -- always just the lob just inserted */
addColAction);
return varLen;
}
Datum
make_tuple_indirect(PG_FUNCTION_ARGS)
{
HeapTupleHeader rec = PG_GETARG_HEAPTUPLEHEADER(0);
HeapTupleData tuple;
int ncolumns;
Datum *values;
bool *nulls;
Oid tupType;
int32 tupTypmod;
TupleDesc tupdesc;
HeapTuple newtup;
int i;
MemoryContext old_context;
/* Extract type info from the tuple itself */
tupType = HeapTupleHeaderGetTypeId(rec);
tupTypmod = HeapTupleHeaderGetTypMod(rec);
tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
ncolumns = tupdesc->natts;
/* Build a temporary HeapTuple control structure */
tuple.t_len = HeapTupleHeaderGetDatumLength(rec);
ItemPointerSetInvalid(&(tuple.t_self));
tuple.t_tableOid = InvalidOid;
tuple.t_data = rec;
values = (Datum *) palloc(ncolumns * sizeof(Datum));
nulls = (bool *) palloc(ncolumns * sizeof(bool));
heap_deform_tuple(&tuple, tupdesc, values, nulls);
old_context = MemoryContextSwitchTo(TopTransactionContext);
for (i = 0; i < ncolumns; i++)
{
struct varlena *attr;
struct varlena *new_attr;
struct varatt_indirect redirect_pointer;
/* only work on existing, not-null varlenas */
if (tupdesc->attrs[i]->attisdropped ||
nulls[i] ||
tupdesc->attrs[i]->attlen != -1)
continue;
attr = (struct varlena *) DatumGetPointer(values[i]);
/* don't recursively indirect */
if (VARATT_IS_EXTERNAL_INDIRECT(attr))
continue;
/* copy datum, so it still lives later */
if (VARATT_IS_EXTERNAL_ONDISK(attr))
attr = heap_tuple_fetch_attr(attr);
else
{
struct varlena *oldattr = attr;
attr = palloc0(VARSIZE_ANY(oldattr));
memcpy(attr, oldattr, VARSIZE_ANY(oldattr));
}
/* build indirection Datum */
new_attr = (struct varlena *) palloc0(INDIRECT_POINTER_SIZE);
redirect_pointer.pointer = attr;
SET_VARTAG_EXTERNAL(new_attr, VARTAG_INDIRECT);
memcpy(VARDATA_EXTERNAL(new_attr), &redirect_pointer,
sizeof(redirect_pointer));
values[i] = PointerGetDatum(new_attr);
}
newtup = heap_form_tuple(tupdesc, values, nulls);
pfree(values);
pfree(nulls);
ReleaseTupleDesc(tupdesc);
MemoryContextSwitchTo(old_context);
PG_RETURN_HEAPTUPLEHEADER(newtup->t_data);
}