static int compute_dest_tuplen(TupleDesc tupdesc, MemTupleBinding *pbind, bool hasnull, Datum *d, bool *isnull)
{
if(pbind)
{
uint32 nullsave_dummy;
return (int) compute_memtuple_size(pbind, d, isnull, hasnull, &nullsave_dummy, true /* aligned */);
}
return heap_compute_data_size(tupdesc, d, isnull);
}
/* ----------
* toast_flatten_tuple_attribute -
*
* If a Datum is of composite type, "flatten" it to contain no toasted fields.
* This must be invoked on any potentially-composite field that is to be
* inserted into a tuple. Doing this preserves the invariant that toasting
* goes only one level deep in a tuple.
*
* Note that flattening does not mean expansion of short-header varlenas,
* so in one sense toasting is allowed within composite datums.
* ----------
*/
Datum
toast_flatten_tuple_attribute(Datum value,
Oid typeId, int32 typeMod)
{
TupleDesc tupleDesc;
HeapTupleHeader olddata;
HeapTupleHeader new_data;
int32 new_len;
int32 new_data_len;
HeapTupleData tmptup;
Form_pg_attribute *att;
int numAttrs;
int i;
bool need_change = false;
bool has_nulls = false;
Datum toast_values[MaxTupleAttributeNumber];
bool toast_isnull[MaxTupleAttributeNumber];
bool toast_free[MaxTupleAttributeNumber];
/*
* See if it's a composite type, and get the tupdesc if so.
*/
tupleDesc = lookup_rowtype_tupdesc_noerror(typeId, typeMod, true);
if (tupleDesc == NULL)
return value; /* not a composite type */
att = tupleDesc->attrs;
numAttrs = tupleDesc->natts;
/*
* Break down the tuple into fields.
*/
olddata = DatumGetHeapTupleHeader(value);
Assert(typeId == HeapTupleHeaderGetTypeId(olddata));
Assert(typeMod == HeapTupleHeaderGetTypMod(olddata));
/* Build a temporary HeapTuple control structure */
tmptup.t_len = HeapTupleHeaderGetDatumLength(olddata);
ItemPointerSetInvalid(&(tmptup.t_self));
tmptup.t_tableOid = InvalidOid;
tmptup.t_data = olddata;
Assert(numAttrs <= MaxTupleAttributeNumber);
heap_deform_tuple(&tmptup, tupleDesc, toast_values, toast_isnull);
memset(toast_free, 0, numAttrs * sizeof(bool));
for (i = 0; i < numAttrs; i++)
{
/*
* Look at non-null varlena attributes
*/
if (toast_isnull[i])
has_nulls = true;
else if (att[i]->attlen == -1)
{
struct varlena *new_value;
new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
if (VARATT_IS_EXTERNAL(new_value) ||
VARATT_IS_COMPRESSED(new_value))
{
new_value = heap_tuple_untoast_attr(new_value);
toast_values[i] = PointerGetDatum(new_value);
toast_free[i] = true;
need_change = true;
}
}
}
/*
* If nothing to untoast, just return the original tuple.
*/
if (!need_change)
{
ReleaseTupleDesc(tupleDesc);
return value;
}
/*
* 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;
new_data = (HeapTupleHeader) palloc0(new_len);
/*
* Put the tuple header and the changed values into place
*/
memcpy(new_data, olddata, olddata->t_hoff);
HeapTupleHeaderSetDatumLength(new_data, new_len);
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);
/*
* Free allocated temp values
*/
for (i = 0; i < numAttrs; i++)
if (toast_free[i])
pfree(DatumGetPointer(toast_values[i]));
ReleaseTupleDesc(tupleDesc);
return PointerGetDatum(new_data);
}
/* ----------
* 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;
}
/*
* Generate a new on-disk tuple to be inserted in a BRIN index.
*
* See brin_form_placeholder_tuple if you touch this.
*/
BrinTuple *
brin_form_tuple(BrinDesc *brdesc, BlockNumber blkno, BrinMemTuple *tuple,
Size *size)
{
Datum *values;
bool *nulls;
bool anynulls = false;
BrinTuple *rettuple;
int keyno;
int idxattno;
uint16 phony_infomask = 0;
bits8 *phony_nullbitmap;
Size len,
hoff,
data_len;
Assert(brdesc->bd_totalstored > 0);
values = (Datum *) palloc(sizeof(Datum) * brdesc->bd_totalstored);
nulls = (bool *) palloc0(sizeof(bool) * brdesc->bd_totalstored);
phony_nullbitmap = (bits8 *)
palloc(sizeof(bits8) * BITMAPLEN(brdesc->bd_totalstored));
/*
* Set up the values/nulls arrays for heap_fill_tuple
*/
idxattno = 0;
for (keyno = 0; keyno < brdesc->bd_tupdesc->natts; keyno++)
{
int datumno;
/*
* "allnulls" is set when there's no nonnull value in any row in the
* column; when this happens, there is no data to store. Thus set the
* nullable bits for all data elements of this column and we're done.
*/
if (tuple->bt_columns[keyno].bv_allnulls)
{
for (datumno = 0;
datumno < brdesc->bd_info[keyno]->oi_nstored;
datumno++)
nulls[idxattno++] = true;
anynulls = true;
continue;
}
/*
* The "hasnulls" bit is set when there are some null values in the
* data. We still need to store a real value, but the presence of
* this means we need a null bitmap.
*/
if (tuple->bt_columns[keyno].bv_hasnulls)
anynulls = true;
for (datumno = 0;
datumno < brdesc->bd_info[keyno]->oi_nstored;
datumno++)
values[idxattno++] = tuple->bt_columns[keyno].bv_values[datumno];
}
/* Assert we did not overrun temp arrays */
Assert(idxattno <= brdesc->bd_totalstored);
/* compute total space needed */
len = SizeOfBrinTuple;
if (anynulls)
{
/*
* We need a double-length bitmap on an on-disk BRIN index tuple; the
* first half stores the "allnulls" bits, the second stores
* "hasnulls".
*/
len += BITMAPLEN(brdesc->bd_tupdesc->natts * 2);
}
len = hoff = MAXALIGN(len);
data_len = heap_compute_data_size(brtuple_disk_tupdesc(brdesc),
values, nulls);
len += data_len;
len = MAXALIGN(len);
rettuple = palloc0(len);
rettuple->bt_blkno = blkno;
rettuple->bt_info = hoff;
/* Assert that hoff fits in the space available */
Assert((rettuple->bt_info & BRIN_OFFSET_MASK) == hoff);
/*
* The infomask and null bitmap as computed by heap_fill_tuple are useless
* to us. However, that function will not accept a null infomask; and we
* need to pass a valid null bitmap so that it will correctly skip
* outputting null attributes in the data area.
*/
heap_fill_tuple(brtuple_disk_tupdesc(brdesc),
values,
nulls,
(char *) rettuple + hoff,
data_len,
&phony_infomask,
phony_nullbitmap);
/* done with these */
pfree(values);
pfree(nulls);
pfree(phony_nullbitmap);
/*
* Now fill in the real null bitmasks. allnulls first.
*/
if (anynulls)
{
bits8 *bitP;
int bitmask;
rettuple->bt_info |= BRIN_NULLS_MASK;
/*
* Note that we reverse the sense of null bits in this module: we
* store a 1 for a null attribute rather than a 0. So we must reverse
* the sense of the att_isnull test in br_deconstruct_tuple as well.
*/
bitP = ((bits8 *) ((char *) rettuple + SizeOfBrinTuple)) - 1;
bitmask = HIGHBIT;
for (keyno = 0; keyno < brdesc->bd_tupdesc->natts; keyno++)
{
if (bitmask != HIGHBIT)
bitmask <<= 1;
else
{
bitP += 1;
*bitP = 0x0;
bitmask = 1;
}
if (!tuple->bt_columns[keyno].bv_allnulls)
continue;
*bitP |= bitmask;
}
/* hasnulls bits follow */
for (keyno = 0; keyno < brdesc->bd_tupdesc->natts; keyno++)
{
if (bitmask != HIGHBIT)
bitmask <<= 1;
else
{
bitP += 1;
*bitP = 0x0;
bitmask = 1;
}
if (!tuple->bt_columns[keyno].bv_hasnulls)
continue;
*bitP |= bitmask;
}
bitP = ((bits8 *) (rettuple + SizeOfBrinTuple)) - 1;
}
if (tuple->bt_placeholder)
rettuple->bt_info |= BRIN_PLACEHOLDER_MASK;
*size = len;
return rettuple;
}
/* ----------------
* 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;
}
/* ----------
* 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
* 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)
{
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;
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];
/*
* 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++)
{
varattrib *old_value;
varattrib *new_value;
if (oldtup != NULL)
{
/*
* For UPDATE get the old and new values of this attribute
*/
old_value = (varattrib *) DatumGetPointer(toast_oldvalues[i]);
new_value = (varattrib *) 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) ||
old_value->va_content.va_external.va_valueid !=
new_value->va_content.va_external.va_valueid ||
old_value->va_content.va_external.va_toastrelid !=
new_value->va_content.va_external.va_toastrelid)
{
/*
* 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';
toast_sizes[i] = VARATT_SIZE(toast_values[i]);
continue;
}
}
}
else
{
/*
* For INSERT simply get the new value
*/
new_value = (varattrib *) 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.
* Expand it to plain (and, probably, toast it again below).
*/
if (VARATT_IS_EXTERNAL(new_value))
{
new_value = heap_tuple_untoast_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] = VARATT_SIZE(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'
* 2: Store attributes with attstorage 'x' or 'e' external
* 3: Inline compress attributes with attstorage 'm'
* 4: Store attributes with attstorage 'm' external
* ----------
*/
maxDataLen = offsetof(HeapTupleHeaderData, t_bits);
if (has_nulls)
maxDataLen += BITMAPLEN(numAttrs);
maxDataLen = TOAST_TUPLE_TARGET - MAXALIGN(maxDataLen);
/*
* Look for attributes with attstorage 'x' to compress
*/
while (MAXALIGN(heap_compute_data_size(tupleDesc,
toast_values, toast_isnull)) >
maxDataLen)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(sizeof(varattrib));
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_EXTENDED(toast_values[i]))
continue;
if (att[i]->attstorage != 'x')
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] = VARATT_SIZE(toast_values[i]);
need_change = true;
need_free = true;
}
else
{
/*
* incompressible data, ignore on subsequent compression passes
*/
toast_action[i] = 'x';
}
}
/*
* Second we look for attributes of attstorage 'x' or 'e' that are still
* inline.
*/
while (MAXALIGN(heap_compute_data_size(tupleDesc,
toast_values, toast_isnull)) >
maxDataLen && rel->rd_rel->reltoastrelid != InvalidOid)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(sizeof(varattrib));
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(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;
/*
* 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]);
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_free[i] = true;
toast_sizes[i] = VARATT_SIZE(toast_values[i]);
need_change = true;
need_free = true;
}
/*
* Round 3 - this time we take attributes with storage 'm' into
* compression
*/
while (MAXALIGN(heap_compute_data_size(tupleDesc,
toast_values, toast_isnull)) >
maxDataLen)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(sizeof(varattrib));
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_EXTENDED(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] = VARATT_SIZE(toast_values[i]);
need_change = true;
need_free = true;
}
else
{
/*
* incompressible data, ignore on subsequent compression passes
*/
toast_action[i] = 'x';
}
}
/*
* Finally we store attributes of type 'm' external
*/
while (MAXALIGN(heap_compute_data_size(tupleDesc,
toast_values, toast_isnull)) >
maxDataLen && rel->rd_rel->reltoastrelid != InvalidOid)
{
int biggest_attno = -1;
int32 biggest_size = MAXALIGN(sizeof(varattrib));
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(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;
/*
* 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]);
if (toast_free[i])
pfree(DatumGetPointer(old_value));
toast_free[i] = true;
toast_sizes[i] = VARATT_SIZE(toast_values[i]);
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;
/*
* 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_len += heap_compute_data_size(tupleDesc,
toast_values, toast_isnull);
/*
* 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;
result_tuple->t_datamcxt = CurrentMemoryContext;
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->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;
}
/*
* heap_form_tuple
* construct a tuple from the given values[] and isnull[] arrays,
* which are of the length indicated by tupleDescriptor->natts
*
* The result is allocated in the current memory context.
*/
HeapTuple
heaptuple_form_to(TupleDesc tupleDescriptor, Datum *values, bool *isnull, HeapTuple dst, uint32 *dstlen)
{
HeapTuple tuple; /* return tuple */
HeapTupleHeader td; /* tuple data */
Size actual_len;
Size len,
data_len;
int hoff;
bool hasnull = false;
Form_pg_attribute *att = tupleDescriptor->attrs;
int numberOfAttributes = tupleDescriptor->natts;
int i;
if (numberOfAttributes > MaxTupleAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("number of columns (%d) exceeds limit (%d)",
numberOfAttributes, MaxTupleAttributeNumber)));
/*
* Check for nulls and embedded tuples; expand any toasted attributes in
* embedded tuples. This preserves the invariant that toasting can only
* go one level deep.
*
* We can skip calling toast_flatten_tuple_attribute() if the attribute
* couldn't possibly be of composite type. All composite datums are
* varlena and have alignment 'd'; furthermore they aren't arrays. Also,
* if an attribute is already toasted, it must have been sent to disk
* already and so cannot contain toasted attributes.
*/
for (i = 0; i < numberOfAttributes; i++)
{
if (isnull[i])
hasnull = true;
else if (att[i]->attlen == -1 &&
att[i]->attalign == 'd' &&
att[i]->attndims == 0 &&
!VARATT_IS_EXTENDED(DatumGetPointer(values[i])))
{
values[i] = toast_flatten_tuple_attribute(values[i],
att[i]->atttypid,
att[i]->atttypmod);
}
}
/*
* Determine total space needed
*/
len = offsetof(HeapTupleHeaderData, t_bits);
if (hasnull)
len += BITMAPLEN(numberOfAttributes);
if (tupleDescriptor->tdhasoid)
len += sizeof(Oid);
hoff = len = MAXALIGN(len); /* align user data safely */
data_len = heap_compute_data_size(tupleDescriptor, values, isnull);
len += data_len;
if (dstlen && (*dstlen) < (HEAPTUPLESIZE + len))
{
*dstlen = HEAPTUPLESIZE + len;
return NULL;
}
if (dstlen)
{
*dstlen = HEAPTUPLESIZE + len;
tuple = dst;
memset(tuple, 0, HEAPTUPLESIZE + len);
}
else
tuple = (HeapTuple) palloc0(HEAPTUPLESIZE + len);
/*
* Allocate and zero the space needed. Note that the tuple body and
* HeapTupleData management structure are allocated in one chunk.
*/
tuple->t_data = td = (HeapTupleHeader) ((char *) tuple + HEAPTUPLESIZE);
/*
* And fill in the information. Note we fill the Datum fields even though
* this tuple may never become a Datum.
*/
tuple->t_len = len;
ItemPointerSetInvalid(&(tuple->t_self));
HeapTupleHeaderSetDatumLength(td, len);
HeapTupleHeaderSetTypeId(td, tupleDescriptor->tdtypeid);
HeapTupleHeaderSetTypMod(td, tupleDescriptor->tdtypmod);
HeapTupleHeaderSetNatts(td, numberOfAttributes);
td->t_hoff = hoff;
if (tupleDescriptor->tdhasoid) /* else leave infomask = 0 */
td->t_infomask = HEAP_HASOID;
actual_len = heap_fill_tuple(tupleDescriptor,
values,
isnull,
(char *) td + hoff,
data_len,
&td->t_infomask,
(hasnull ? td->t_bits : NULL));
Assert(data_len == actual_len);
Assert(!is_heaptuple_memtuple(tuple));
return tuple;
}
/*
* heap_form_minimal_tuple
* construct a MinimalTuple from the given values[] and isnull[] arrays,
* which are of the length indicated by tupleDescriptor->natts
*
* This is exactly like heap_form_tuple() except that the result is a
* "minimal" tuple lacking a HeapTupleData header as well as room for system
* columns.
*
* The result is allocated in the current memory context.
*/
MinimalTuple
heap_form_minimal_tuple(TupleDesc tupleDescriptor,
Datum *values,
bool *isnull)
{
MinimalTuple tuple; /* return tuple */
Size len,
data_len;
int hoff;
bool hasnull = false;
Form_pg_attribute *att = tupleDescriptor->attrs;
int numberOfAttributes = tupleDescriptor->natts;
int i;
if (numberOfAttributes > MaxTupleAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("number of columns (%d) exceeds limit (%d)",
numberOfAttributes, MaxTupleAttributeNumber)));
/*
* Check for nulls and embedded tuples; expand any toasted attributes in
* embedded tuples. This preserves the invariant that toasting can only
* go one level deep.
*
* We can skip calling toast_flatten_tuple_attribute() if the attribute
* couldn't possibly be of composite type. All composite datums are
* varlena and have alignment 'd'; furthermore they aren't arrays. Also,
* if an attribute is already toasted, it must have been sent to disk
* already and so cannot contain toasted attributes.
*/
for (i = 0; i < numberOfAttributes; i++)
{
if (isnull[i])
hasnull = true;
else if (att[i]->attlen == -1 &&
att[i]->attalign == 'd' &&
att[i]->attndims == 0 &&
!VARATT_IS_EXTENDED(values[i]))
{
values[i] = toast_flatten_tuple_attribute(values[i],
att[i]->atttypid,
att[i]->atttypmod);
}
}
/*
* Determine total space needed
*/
len = offsetof(MinimalTupleData, t_bits);
if (hasnull)
len += BITMAPLEN(numberOfAttributes);
if (tupleDescriptor->tdhasoid)
len += sizeof(Oid);
hoff = len = MAXALIGN(len); /* align user data safely */
data_len = heap_compute_data_size(tupleDescriptor, values, isnull);
len += data_len;
/*
* Allocate and zero the space needed.
*/
tuple = (MinimalTuple) palloc0(len);
/*
* And fill in the information.
*/
tuple->t_len = len;
HeapTupleHeaderSetNatts(tuple, numberOfAttributes);
tuple->t_hoff = hoff + MINIMAL_TUPLE_OFFSET;
if (tupleDescriptor->tdhasoid) /* else leave infomask = 0 */
tuple->t_infomask = HEAP_HASOID;
heap_fill_tuple(tupleDescriptor,
values,
isnull,
(char *) tuple + hoff,
data_len,
&tuple->t_infomask,
(hasnull ? tuple->t_bits : NULL));
return tuple;
}
