1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
/*-------------------------------------------------------------------------
*
* pg_ndistinct.c
* pg_ndistinct data type support.
*
* Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/utils/adt/pg_ndistinct.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "lib/stringinfo.h"
#include "statistics/extended_stats_internal.h"
#include "utils/fmgrprotos.h"
/*
* pg_ndistinct_in
* input routine for type pg_ndistinct
*
* pg_ndistinct is real enough to be a table column, but it has no
* operations of its own, and disallows input (just like pg_node_tree).
*/
Datum
pg_ndistinct_in(PG_FUNCTION_ARGS)
{
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot accept a value of type %s", "pg_ndistinct")));
PG_RETURN_VOID(); /* keep compiler quiet */
}
/*
* pg_ndistinct_out
* output routine for type pg_ndistinct
*
* Produces a human-readable representation of the value.
*/
Datum
pg_ndistinct_out(PG_FUNCTION_ARGS)
{
bytea *data = PG_GETARG_BYTEA_PP(0);
MVNDistinct *ndist = statext_ndistinct_deserialize(data);
int i;
StringInfoData str;
initStringInfo(&str);
appendStringInfoChar(&str, '{');
for (i = 0; i < ndist->nitems; i++)
{
int j;
MVNDistinctItem item = ndist->items[i];
if (i > 0)
appendStringInfoString(&str, ", ");
for (j = 0; j < item.nattributes; j++)
{
AttrNumber attnum = item.attributes[j];
appendStringInfo(&str, "%s%d", (j == 0) ? "\"" : ", ", attnum);
}
appendStringInfo(&str, "\": %d", (int) item.ndistinct);
}
appendStringInfoChar(&str, '}');
PG_RETURN_CSTRING(str.data);
}
/*
* pg_ndistinct_recv
* binary input routine for type pg_ndistinct
*/
Datum
pg_ndistinct_recv(PG_FUNCTION_ARGS)
{
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot accept a value of type %s", "pg_ndistinct")));
PG_RETURN_VOID(); /* keep compiler quiet */
}
/*
* pg_ndistinct_send
* binary output routine for type pg_ndistinct
*
* n-distinct is serialized into a bytea value, so let's send that.
*/
Datum
pg_ndistinct_send(PG_FUNCTION_ARGS)
{
return byteasend(fcinfo);
}
|
