database/postgres
database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-05-18 17:41:14 +03:00
Code

Back-port heap_deformtuple() into 7.4 branch; needed for planned fix for

Browse Source 
CLUSTER failure after ALTER TABLE SET WITHOUT OIDS.
This commit is contained in:
Tom Lane 2005-02-06 20:15:32 +00:00
parent 6508888ded
commit 5bb38455e6
2 changed files with 91 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

124
src/backend/access/common/heaptuple.c
View File

@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/common/heaptuple.c,v 1.87 2003/09/25 06:57:56 petere Exp $
* $Header: /cvsroot/pgsql/src/backend/access/common/heaptuple.c,v 1.87.2.1 2005/02/06 20:15:32 tgl Exp $
*
* NOTES
* The old interface functions have been converted to macros
@ -512,41 +512,6 @@ heap_copytuple_with_tuple(HeapTuple src, HeapTuple dest)
memcpy((char *) dest->t_data, (char *) src->t_data, src->t_len);
}
#ifdef NOT_USED
/* ----------------
* heap_deformtuple
*
* the inverse of heap_formtuple (see below)
* ----------------
*/
void
heap_deformtuple(HeapTuple tuple,
TupleDesc tdesc,
Datum *values,
char *nulls)
{
int i;
int natts;
Assert(HeapTupleIsValid(tuple));
natts = tuple->t_natts;
for (i = 0; i < natts; i++)
{
bool isnull;
values[i] = heap_getattr(tuple,
i + 1,
tdesc,
&isnull);
if (isnull)
nulls[i] = 'n';
else
nulls[i] = ' ';
}
}
#endif
/* ----------------
* heap_formtuple
*
@ -712,6 +677,93 @@ heap_modifytuple(HeapTuple tuple,
return newTuple;
}
/* ----------------
* heap_deformtuple
*
* Given a tuple, extract data into values/nulls arrays; this is
* the inverse of heap_formtuple.
*
* Storage for the values/nulls arrays is provided by the caller;
* it should be sized according to tupleDesc->natts not tuple->t_natts.
*
* Note that for pass-by-reference datatypes, the pointer placed
* in the Datum will point into the given tuple.
*
* When all or most of a tuple's fields need to be extracted,
* this routine will be significantly quicker than a loop around
* heap_getattr; the loop will become O(N^2) as soon as any
* noncacheable attribute offsets are involved.
* ----------------
*/
void
heap_deformtuple(HeapTuple tuple,
TupleDesc tupleDesc,
Datum *values,
char *nulls)
{
HeapTupleHeader tup = tuple->t_data;
Form_pg_attribute *att = tupleDesc->attrs;
int tdesc_natts = tupleDesc->natts;
int natts; /* number of atts to extract */
int attnum;
char *tp; /* ptr to tuple data */
long off; /* offset in tuple data */
bits8 *bp = tup->t_bits; /* ptr to null bitmask in tuple */
bool slow = false; /* can we use/set attcacheoff? */
natts = tup->t_natts;
/*
* In inheritance situations, it is possible that the given tuple
* actually has more fields than the caller is expecting. Don't run
* off the end of the caller's arrays.
*/
natts = Min(natts, tdesc_natts);
tp = (char *) tup + tup->t_hoff;
off = 0;
for (attnum = 0; attnum < natts; attnum++)
{
if (!HeapTupleNoNulls(tuple) && att_isnull(attnum, bp))
{
values[attnum] = (Datum) 0;
nulls[attnum] = 'n';
slow = true; /* can't use attcacheoff anymore */
continue;
}
nulls[attnum] = ' ';
if (!slow && att[attnum]->attcacheoff >= 0)
off = att[attnum]->attcacheoff;
else
{
off = att_align(off, att[attnum]->attalign);
if (!slow)
att[attnum]->attcacheoff = off;
}
values[attnum] = fetchatt(att[attnum], tp + off);
off = att_addlength(off, att[attnum]->attlen, tp + off);
if (att[attnum]->attlen <= 0)
slow = true; /* can't use attcacheoff anymore */
}
/*
* If tuple doesn't have all the atts indicated by tupleDesc, read the
* rest as null
*/
for (; attnum < tdesc_natts; attnum++)
{
values[attnum] = (Datum) 0;
nulls[attnum] = 'n';
}
}
/* ----------------
* heap_freetuple

4
src/include/access/heapam.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: heapam.h,v 1.85 2003/10/01 21:30:52 tgl Exp $
* $Id: heapam.h,v 1.85.2.1 2005/02/06 20:15:29 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -192,6 +192,8 @@ extern HeapTuple heap_formtuple(TupleDesc tupleDescriptor,
Datum *value, char *nulls);
extern HeapTuple heap_modifytuple(HeapTuple tuple,
Relation relation, Datum *replValue, char *replNull, char *repl);
extern void heap_deformtuple(HeapTuple tuple, TupleDesc tupleDesc,
Datum *values, char *nulls);
extern void heap_freetuple(HeapTuple tuple);
extern HeapTuple heap_addheader(int natts, bool withoid, Size structlen, void *structure);