Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commita923602

Browse files
committed
Add pg_column_size() to return storage size of a column, including
possible compression.Mark Kirkwood
1 parentb9cb132 commita923602

File tree

6 files changed

+114
-6
lines changed

6 files changed

+114
-6
lines changed

‎doc/src/sgml/func.sgml‎

Lines changed: 9 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
<!--
2-
$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.262 2005/06/29 01:52:56 momjian Exp $
2+
$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.263 2005/07/06 19:02:52 momjian Exp $
33
PostgreSQL documentation
44
-->
55

@@ -2186,6 +2186,14 @@ PostgreSQL documentation
21862186
<entry><literal>5</literal></entry>
21872187
</row>
21882188

2189+
<row>
2190+
<entry><literal><function>pg_column_size</function>(<parameter>string</parameter>)</literal></entry>
2191+
<entry><type>integer</type></entry>
2192+
<entry>Number of bytes required to store the value, which might be compressed</entry>
2193+
<entry><literal>pg_column_size('jo\\000se'::bytea)</literal></entry>
2194+
<entry><literal>5</literal></entry>
2195+
</row>
2196+
21892197
<row>
21902198
<entry><literal><function>position</function>(<parameter>substring</parameter> in <parameter>string</parameter>)</literal></entry>
21912199
<entry><type>integer</type></entry>

‎src/backend/access/heap/tuptoaster.c‎

Lines changed: 43 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.49 2005/03/21 01:23:58 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.50 2005/07/06 19:02:52 momjian Exp $
1212
*
1313
*
1414
* INTERFACE ROUTINES
@@ -1436,3 +1436,45 @@ toast_fetch_datum_slice(varattrib *attr, int32 sliceoffset, int32 length)
14361436

14371437
returnresult;
14381438
}
1439+
1440+
/* ----------
1441+
* toast_datum_size
1442+
*
1443+
*Show the (possibly compressed) size of a datum
1444+
* ----------
1445+
*/
1446+
Size
1447+
toast_datum_size(Datumvalue)
1448+
{
1449+
1450+
varattrib*attr= (varattrib*)DatumGetPointer(value);
1451+
Sizeresult;
1452+
1453+
if (VARATT_IS_EXTERNAL(attr))
1454+
{
1455+
/*
1456+
* Attribute is stored externally - If it is compressed too,
1457+
* then we need to get the external datum and calculate its size,
1458+
* otherwise we just use the external rawsize.
1459+
*/
1460+
if (VARATT_IS_COMPRESSED(attr))
1461+
{
1462+
varattrib*attrext=toast_fetch_datum(attr);
1463+
result=VARSIZE(attrext);
1464+
pfree(attrext);
1465+
}
1466+
else
1467+
result=attr->va_content.va_external.va_rawsize;
1468+
}
1469+
else
1470+
{
1471+
/*
1472+
* Attribute is stored inline either compressed or not, just
1473+
* calculate the size of the datum in either case.
1474+
*/
1475+
result=VARSIZE(attr);
1476+
}
1477+
1478+
returnresult;
1479+
1480+
}

‎src/backend/utils/adt/varlena.c‎

Lines changed: 46 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.124 2005/07/04 18:56:44 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.125 2005/07/06 19:02:52 momjian Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -28,6 +28,7 @@
2828
#include"utils/builtins.h"
2929
#include"utils/lsyscache.h"
3030
#include"utils/pg_locale.h"
31+
#include"utils/syscache.h"
3132

3233

3334
typedefstructvarlenaunknown;
@@ -2348,3 +2349,47 @@ md5_bytea(PG_FUNCTION_ARGS)
23482349
result_text=PG_STR_GET_TEXT(hexsum);
23492350
PG_RETURN_TEXT_P(result_text);
23502351
}
2352+
2353+
/*
2354+
* Return the length of a datum, possibly compressed
2355+
*/
2356+
Datum
2357+
pg_column_size(PG_FUNCTION_ARGS)
2358+
{
2359+
Datumvalue=PG_GETARG_DATUM(0);
2360+
intresult;
2361+
2362+
/*fn_extra stores the fixed column length, or -1 for varlena. */
2363+
if (fcinfo->flinfo->fn_extra==NULL)/* first call? */
2364+
{
2365+
/* On the first call lookup the datatype of the supplied argument */
2366+
Oidargtypeid=get_fn_expr_argtype(fcinfo->flinfo,0);
2367+
HeapTupletp;
2368+
inttyplen;
2369+
2370+
tp=SearchSysCache(TYPEOID,
2371+
ObjectIdGetDatum(argtypeid),
2372+
0,0,0);
2373+
if (!HeapTupleIsValid(tp))
2374+
{
2375+
/* Oid not in pg_type, should never happen. */
2376+
ereport(ERROR,
2377+
(errcode(ERRCODE_INTERNAL_ERROR),
2378+
errmsg("invalid typid: %u",argtypeid)));
2379+
}
2380+
2381+
typlen= ((Form_pg_type)GETSTRUCT(tp))->typlen;
2382+
ReleaseSysCache(tp);
2383+
fcinfo->flinfo->fn_extra=MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
2384+
sizeof(int));
2385+
*(int*)fcinfo->flinfo->fn_extra=typlen;
2386+
}
2387+
2388+
if (*(int*)fcinfo->flinfo->fn_extra!=-1)
2389+
PG_RETURN_INT32(*(int*)fcinfo->flinfo->fn_extra);
2390+
else
2391+
{
2392+
result=toast_datum_size(value)-VARHDRSZ;
2393+
PG_RETURN_INT32(result);
2394+
}
2395+
}

‎src/include/access/tuptoaster.h‎

Lines changed: 9 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -6,7 +6,7 @@
66
*
77
* Copyright (c) 2000-2005, PostgreSQL Global Development Group
88
*
9-
* $PostgreSQL: pgsql/src/include/access/tuptoaster.h,v 1.22 2005/03/21 01:24:04 tgl Exp $
9+
* $PostgreSQL: pgsql/src/include/access/tuptoaster.h,v 1.23 2005/07/06 19:02:53 momjian Exp $
1010
*
1111
*-------------------------------------------------------------------------
1212
*/
@@ -138,4 +138,12 @@ extern Datum toast_compress_datum(Datum value);
138138
*/
139139
externSizetoast_raw_datum_size(Datumvalue);
140140

141+
/* ----------
142+
* toast_datum_size -
143+
*
144+
*Return the storage size of a varlena datum
145+
* ----------
146+
*/
147+
externSizetoast_datum_size(Datumvalue);
148+
141149
#endif/* TUPTOASTER_H */

‎src/include/catalog/pg_proc.h‎

Lines changed: 5 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
88
* Portions Copyright (c) 1994, Regents of the University of California
99
*
10-
* $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.373 2005/07/01 19:19:03 tgl Exp $
10+
* $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.374 2005/07/06 19:02:53 momjian Exp $
1111
*
1212
* NOTES
1313
* The script catalog/genbki.sh reads this file and generates .bki
@@ -3658,6 +3658,10 @@ DESCR("current value from last used sequence");
36583658
DATA(insertOID=2560 (pg_postmaster_start_timePGNSPPGUID12fftfs01184""_null__null__null_pgsql_postmaster_start_time-_null_ ));
36593659
DESCR("postmaster start time");
36603660

3661+
/* Column storage size */
3662+
DATA(insertOID=1269 (pg_column_sizePGNSPPGUID12fftfi123"2276"_null__null__null_pg_column_size-_null_ ));
3663+
DESCR("bytes required to store the value, perhaps with compression");
3664+
36613665
/* new functions for Y-direction rtree opclasses */
36623666
DATA(insertOID=2562 (box_belowPGNSPPGUID12fftfi216"603 603"_null__null__null_box_below-_null_ ));
36633667
DESCR("is below");

‎src/include/utils/builtins.h‎

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
88
* Portions Copyright (c) 1994, Regents of the University of California
99
*
10-
* $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.258 2005/06/17 22:32:50 tgl Exp $
10+
* $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.259 2005/07/06 19:02:54 momjian Exp $
1111
*
1212
*-------------------------------------------------------------------------
1313
*/
@@ -601,6 +601,7 @@ extern Datum byteacat(PG_FUNCTION_ARGS);
601601
externDatumbyteapos(PG_FUNCTION_ARGS);
602602
externDatumbytea_substr(PG_FUNCTION_ARGS);
603603
externDatumbytea_substr_no_len(PG_FUNCTION_ARGS);
604+
externDatumpg_column_size(PG_FUNCTION_ARGS);
604605

605606
/* version.c */
606607
externDatumpgsql_version(PG_FUNCTION_ARGS);

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp