Temporary fix to make TOAST vacuum-safe. All values are forced to be

in memory (plain or compressed) in the tuple returned from the heap-am.
So no index will ever contain an external reference.

Jan

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 6a7f9ee1e2c609a9757f077433d8011c64b9feaa..16d2ed470eb60fdf7540dbb93c3097d4042ff4d3 100644 (file)
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.79 2000/07/04 17:11:40 wieck Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.80 2000/07/21 10:31:30 wieck Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1274,6 +1274,10 @@ Oid
 heap_insert(Relation relation, HeapTuple tup)
 {
    Buffer buffer;
+#ifndef TOAST_INDICES
+   HeapTupleHeader plaintdata = NULL;
+   int32           plaintlen = 0;
+#endif
 
    /* increment access statistics */
    tup->tableOid = relation->rd_id;
@@ -1309,7 +1313,11 @@ heap_insert(Relation relation, HeapTuple tup)
     */
     if (HeapTupleHasExtended(tup) ||
                (MAXALIGN(tup->t_len) > (MaxTupleSize / 4)))
+#ifdef TOAST_INDICES
        heap_tuple_toast_attrs(relation, tup, NULL);
+#else
+       heap_tuple_toast_attrs(relation, tup, NULL, &plaintdata, &plaintlen);
+#endif
 #endif
 
    /* Find buffer for this tuple */
@@ -1347,6 +1355,16 @@ heap_insert(Relation relation, HeapTuple tup)
    if (IsSystemRelationName(RelationGetRelationName(relation)))
        RelationMark4RollbackHeapTuple(relation, tup);
 
+#ifndef TOAST_INDICES
+    if (plaintdata != NULL && tup->t_data != plaintdata)
+   {
+       if (tup->t_datamcxt != NULL && (char *) (tup->t_data) !=
+                   ((char *) tup + HEAPTUPLESIZE))
+           pfree(tup->t_data);
+       tup->t_data = plaintdata;
+       tup->t_len  = plaintlen;
+   }
+#endif
    return tup->t_data->t_oid;
 }
 
@@ -1461,7 +1479,11 @@ l1:
     * ----------
     */
    if (HeapTupleHasExtended(&tp))
+#ifdef TOAST_INDICES
        heap_tuple_toast_attrs(relation, NULL, &(tp));
+#else
+       heap_tuple_toast_attrs(relation, NULL, &(tp), NULL, NULL);
+#endif
 #endif
 
    LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
@@ -1486,6 +1508,10 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
    PageHeader  dp;
    Buffer      buffer, newbuf;
    int         result;
+#ifndef TOAST_INDICES
+   HeapTupleHeader plaintdata = NULL;
+   int32           plaintlen  = 0;
+#endif
 
    newtup->tableOid = relation->rd_id;
    /* increment access statistics */
@@ -1574,7 +1600,11 @@ l2:
    if (HeapTupleHasExtended(&oldtup) || 
            HeapTupleHasExtended(newtup) ||
            (MAXALIGN(newtup->t_len) > (MaxTupleSize / 4)))
+#ifdef TOAST_INDICES
        heap_tuple_toast_attrs(relation, newtup, &oldtup);
+#else
+       heap_tuple_toast_attrs(relation, newtup, &oldtup, &plaintdata, &plaintlen);
+#endif
 #endif
 
    /* Find buffer for new tuple */
@@ -1637,6 +1667,17 @@ l2:
    RelationInvalidateHeapTuple(relation, &oldtup);
    RelationMark4RollbackHeapTuple(relation, newtup);
 
+#ifndef TOAST_INDICES
+    if (plaintdata != NULL && newtup->t_data != plaintdata)
+   {
+       if (newtup->t_datamcxt != NULL && (char *) (newtup->t_data) !=
+                   ((char *) newtup + HEAPTUPLESIZE))
+           pfree(newtup->t_data);
+       newtup->t_data = plaintdata;
+       newtup->t_len  = plaintlen;
+   }
+#endif
+
    return HeapTupleMayBeUpdated;
 }
 

diff --git a/src/backend/access/heap/tuptoaster.c b/src/backend/access/heap/tuptoaster.c
index 8abadaa7355eb5c75bbfed4ae9f071e47ef5af21..b1cd2601f99e587f3399762d04ff9e6d95a16f4a 100644 (file)
--- a/src/backend/access/heap/tuptoaster.c
+++ b/src/backend/access/heap/tuptoaster.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/access/heap/tuptoaster.c,v 1.7 2000/07/11 12:32:03 wieck Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/access/heap/tuptoaster.c,v 1.8 2000/07/21 10:31:30 wieck Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -43,8 +43,14 @@
 
 static void            toast_delete(Relation rel, HeapTuple oldtup);
 static void            toast_delete_datum(Relation rel, Datum value);
+#ifdef TOAST_INDICES
 static void            toast_insert_or_update(Relation rel, HeapTuple newtup,
                                HeapTuple oldtup);
+#else
+static void            toast_insert_or_update(Relation rel, HeapTuple newtup,
+                               HeapTuple oldtup, HeapTupleHeader *plaintdata,
+                               int32 *plaintlen);
+#endif
 static Datum       toast_compress_datum(Datum value);
 static Datum       toast_save_datum(Relation rel, Oid mainoid, int16 attno, Datum value);
                                
@@ -59,6 +65,7 @@ static varattrib   *toast_fetch_datum(varattrib *attr);
  * Calls the appropriate event specific action.
  * ----------
  */
+#ifdef TOAST_INDICES
 void
 heap_tuple_toast_attrs(Relation rel, HeapTuple newtup, HeapTuple oldtup)
 {
@@ -67,6 +74,17 @@ heap_tuple_toast_attrs(Relation rel, HeapTuple newtup, HeapTuple oldtup)
    else
        toast_insert_or_update(rel, newtup, oldtup);
 }
+#else
+void
+heap_tuple_toast_attrs(Relation rel, HeapTuple newtup, 
+           HeapTuple oldtup, HeapTupleHeader *plaintdata, int32 *plaintlen)
+{
+   if (newtup == NULL)
+       toast_delete(rel, oldtup);
+   else
+       toast_insert_or_update(rel, newtup, oldtup, plaintdata, plaintlen);
+}
+#endif
 
 
 /* ----------
@@ -181,7 +199,12 @@ toast_delete(Relation rel, HeapTuple oldtup)
  * ----------
  */
 static void
+#ifdef TOAST_INDICES
 toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
+#else
+toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup,
+               HeapTupleHeader *plaintdata, int32 *plaintlen)
+#endif
 {
    TupleDesc           tupleDesc;
    Form_pg_attribute  *att;
@@ -204,6 +227,12 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
    bool                toast_free[MaxHeapAttributeNumber];
    bool                toast_delold[MaxHeapAttributeNumber];
 
+#ifndef TOAST_INDICES
+   bool                need_plain  = false;
+   Datum               toast_plains[MaxHeapAttributeNumber];
+   bool                toast_freeplain[MaxHeapAttributeNumber];
+#endif
+
    /* ----------
     * Get the tuple descriptor, the number of and attribute
     * descriptors and the location of the tuple values.
@@ -217,10 +246,11 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
     * Then collect information about the values given
     * ----------
     */
-   memset(toast_action, ' ', numAttrs * sizeof(char));
-   memset(toast_nulls,  ' ', numAttrs * sizeof(char));
-   memset(toast_free,   0,   numAttrs * sizeof(bool));
-   memset(toast_delold, 0,   numAttrs * sizeof(bool));
+   memset(toast_action,    ' ', numAttrs * sizeof(char));
+   memset(toast_nulls,     ' ', numAttrs * sizeof(char));
+   memset(toast_free,      0,   numAttrs * sizeof(bool));
+   memset(toast_freeplain, 0,   numAttrs * sizeof(bool));
+   memset(toast_delold,    0,   numAttrs * sizeof(bool));
    for (i = 0; i < numAttrs; i++)
    {
        varattrib      *old_value;
@@ -270,6 +300,25 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
                     */
                    toast_action[i] = 'p';
                    toast_sizes[i] = VARATT_SIZE(toast_values[i]);
+
+#ifndef TOAST_INDICES
+                   /* ----------
+                    * But the tuple returned by the heap-am
+                    * function must not contain external references.
+                    * So we have to construct another plain tuple
+                    * later.
+                    * ----------
+                    */
+                   if (att[i]->attstorage == 'x' || att[i]->attstorage == 'm')
+                       toast_plains[i] = PointerGetDatum(
+                               toast_fetch_datum(new_value));
+                   else
+                       toast_plains[i] = PointerGetDatum(
+                               heap_tuple_untoast_attr(new_value));
+                   toast_freeplain[i] = true;
+                   need_plain = true;
+#endif
+
                    continue;
                }
            }
@@ -320,10 +369,17 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
            {
                toast_values[i] = PointerGetDatum(heap_tuple_untoast_attr(
                    (varattrib *)DatumGetPointer(toast_values[i])));
+#ifndef TOAST_INDICES
+               toast_plains[i] = toast_values[i];
+#endif
                toast_free[i] = true;
                need_change = true;
                need_free = true;
            }
+#ifndef TOAST_INDICES
+           else
+               toast_plains[i] = toast_values[i];
+#endif
 
            /* ----------
             * Remember the size of this attribute
@@ -339,6 +395,9 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
             */
            toast_action[i] = 'p';
            toast_sizes[i]  = att[i]->attlen;
+#ifndef TOAST_INDICES
+           toast_plains[i] = toast_values[i];
+#endif
        }
    }
 
@@ -397,6 +456,9 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
        old_value           = toast_values[i];
 
        toast_values[i]     = toast_compress_datum(toast_values[i]);
+#ifndef TOAST_INDICES
+       toast_plains[i]     = toast_values[i];
+#endif
                                    
        if (toast_free[i])
            pfree(DatumGetPointer(old_value));
@@ -454,8 +516,14 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
                                    newtup->t_data->t_oid,
                                    i + 1,
                                    toast_values[i]);
+#ifndef TOAST_INDICES
+       need_plain = true;
+       if (toast_free[i])
+           toast_freeplain[i] = true;
+#else
        if (toast_free[i])
            pfree(DatumGetPointer(old_value));
+#endif
 
        toast_free[i]       = true;
        toast_sizes[i]      = VARATT_SIZE(toast_values[i]);
@@ -506,6 +574,9 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
        old_value           = toast_values[i];
 
        toast_values[i]     = toast_compress_datum(toast_values[i]);
+#ifndef TOAST_INDICES
+       toast_plains[i]     = toast_values[i];
+#endif
                                    
        if (toast_free[i])
            pfree(DatumGetPointer(old_value));
@@ -562,8 +633,14 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
                                    newtup->t_data->t_oid,
                                    i + 1,
                                    toast_values[i]);
+#ifndef TOAST_INDICES
+       need_plain = true;
+       if (toast_free[i])
+           toast_freeplain[i] = true;
+#else
        if (toast_free[i])
            pfree(DatumGetPointer(old_value));
+#endif
 
        toast_free[i]       = true;
        toast_sizes[i]      = VARATT_SIZE(toast_values[i]);
@@ -637,14 +714,77 @@ toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup)
    }
 
 
+#ifndef TOAST_INDICES
+   /* ----------
+    * In the case we toasted any values, we need to build
+    * a new heap tuple with the changed values.
+    * ----------
+    */
+   if (need_plain)
+   {
+       int32           new_len;
+       MemoryContext   oldcxt;
+
+       /* ----------
+        * Calculate the new size of the tuple
+        * ----------
+        */
+       new_len = offsetof(HeapTupleHeaderData, t_bits);
+       if (has_nulls)
+           new_len += BITMAPLEN(numAttrs);
+       new_len = MAXALIGN(new_len);
+       new_len += ComputeDataSize(tupleDesc, toast_plains, toast_nulls);
+
+       /* ----------
+        * Switch to the memory context of the HeapTuple structure
+        * and allocate the new tuple.
+        * ----------
+        */
+       oldcxt = MemoryContextSwitchTo(newtup->t_datamcxt);
+       *plaintdata = palloc(new_len);
+       *plaintlen  = new_len;
+
+       /* ----------
+        * Put the tuple header and the changed values into place
+        * ----------
+        */
+       memcpy(*plaintdata, newtup->t_data, newtup->t_data->t_hoff);
+
+       DataFill((char *)(MAXALIGN((long)(*plaintdata) +
+                       offsetof(HeapTupleHeaderData, t_bits) + 
+                       ((has_nulls) ? BITMAPLEN(numAttrs) : 0))),
+               tupleDesc,
+               toast_plains,
+               toast_nulls,
+               &((*plaintdata)->t_infomask),
+               has_nulls ? (*plaintdata)->t_bits : NULL);
+
+       /* ----------
+        * Switch back to the old memory context
+        * ----------
+        */
+       MemoryContextSwitchTo(oldcxt);
+   }
+#endif
+
+
    /* ----------
     * Free allocated temp values
     * ----------
     */
    if (need_free)
        for (i = 0; i < numAttrs; i++)
+#ifndef TOAST_INDICES
+       {
+           if (toast_free[i])
+               pfree(DatumGetPointer(toast_values[i]));
+           if (toast_freeplain[i])
+               pfree(DatumGetPointer(toast_plains[i]));
+       }
+#else
            if (toast_free[i])
                pfree(DatumGetPointer(toast_values[i]));
+#endif
 
    /* ----------
     * Delete external values from the old tuple

diff --git a/src/include/access/tuptoaster.h b/src/include/access/tuptoaster.h
index da38f65385c5865b617377ae925addc529aa2852..a84df07c68649f8c5f0b0d6b7e61f221882d6a76 100644 (file)
--- a/src/include/access/tuptoaster.h
+++ b/src/include/access/tuptoaster.h
@@ -6,7 +6,7 @@
  *
  * Copyright (c) 2000, PostgreSQL Development Team
  *
- * $Id: tuptoaster.h,v 1.5 2000/07/04 06:11:50 tgl Exp $
+ * $Id: tuptoaster.h,v 1.6 2000/07/21 10:31:31 wieck Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -20,6 +20,14 @@
 #include "access/tupmacs.h"
 #include "utils/rel.h"
 
+/*
+ * DO NOT ENABLE THIS
+ * until we have crash safe file versioning and you've
+ * changed VACUUM to recreate indices that use possibly
+ * toasted values. 2000/07/20 Jan
+ */
+#undef TOAST_INDICES
+
 
 #define    TOAST_MAX_CHUNK_SIZE    ((MaxTupleSize -                            \
                MAXALIGN(                                               \
@@ -29,8 +37,14 @@
                    MAXALIGN(VARHDRSZ))) / 4)
 
 
+#ifdef TOAST_INDICES
 extern void heap_tuple_toast_attrs(Relation rel,
                HeapTuple newtup, HeapTuple oldtup);
+#else
+extern void heap_tuple_toast_attrs(Relation rel,
+               HeapTuple newtup, HeapTuple oldtup, 
+               HeapTupleHeader *plaintdata, int32 *plaintlen);
+#endif
 
 extern varattrib *heap_tuple_untoast_attr(varattrib * attr);