diff options
Diffstat (limited to 'src/include/access/heapam.h')
| -rw-r--r-- | src/include/access/heapam.h | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h index f16a3bec536..9fdb9af8e75 100644 --- a/src/include/access/heapam.h +++ b/src/include/access/heapam.h @@ -6,7 +6,7 @@ * * Copyright (c) 1994, Regents of the University of California * - * $Id: heapam.h,v 1.7 1997/08/19 21:37:30 momjian Exp $ + * $Id: heapam.h,v 1.8 1997/08/26 23:31:53 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -78,6 +78,30 @@ typedef HeapAccessStatisticsData *HeapAccessStatistics; #define IncrHeapAccessStat(x) \ (heap_access_stats == NULL ? 0 : (heap_access_stats->x)++) +/* ---------------- + * heap_getattr + * + * Find a particular field in a row represented as a heap tuple. + * We return a pointer into that heap tuple, which points to the + * first byte of the value of the field in question. + * + * If the field in question has a NULL value, we return a null + * pointer and return <*isnull> == true. Otherwise, we return + * <*isnull> == false. + * + * <tup> is the pointer to the heap tuple. <attnum> is the attribute + * number of the column (field) caller wants. <tupleDesc> is a + * pointer to the structure describing the row and all its fields. + * ---------------- */ +#define heap_getattr(tup, b, attnum, tupleDesc, isnull) \ + (AssertMacro((tup) != NULL) ? \ + ((attnum) > (int) (tup)->t_natts) ? \ + (((isnull) ? (*(isnull) = true) : NULL), (char *) NULL) : \ + ((attnum) > 0) ? \ + fastgetattr((tup), (attnum), (tupleDesc), (isnull)) : \ + (((isnull) ? (*(isnull) = false) : NULL), heap_getsysattr((tup), (b), (attnum))) : \ + (char *) NULL) + extern HeapAccessStatistics heap_access_stats; /* in stats.c */ /* ---------------- @@ -114,10 +138,9 @@ extern void DataFill(char *data, TupleDesc tupleDesc, extern int heap_attisnull(HeapTuple tup, int attnum); extern int heap_sysattrlen(AttrNumber attno); extern bool heap_sysattrbyval(AttrNumber attno); +extern char *heap_getsysattr(HeapTuple tup, Buffer b, int attnum); extern char *fastgetattr(HeapTuple tup, int attnum, TupleDesc att, bool *isnull); -extern char *heap_getattr(HeapTuple tup, Buffer b, int attnum, - TupleDesc att, bool *isnull); extern HeapTuple heap_copytuple(HeapTuple tuple); extern HeapTuple heap_formtuple(TupleDesc tupleDescriptor, Datum value[], char nulls[]); |