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

Commiteae456c

Browse files
committed
Add a notion of a 'catalog version number' that can indicate
when an initdb-forcing change has been applied within a development cycle.PG_VERSION serves this purpose for official releases, but we can't bumpthe PG_VERSION number every time we make a change to the catalogs duringdevelopment. Instead, increase the catalog version number to warn otherdevelopers that you've made an incompatible change. See my mail topghackers for more info.
1 parent9efee18 commiteae456c

File tree

3 files changed

+90
-11
lines changed

3 files changed

+90
-11
lines changed

‎src/backend/access/transam/Makefile

Lines changed: 5 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -4,7 +4,7 @@
44
# Makefile for access/transam
55
#
66
# IDENTIFICATION
7-
# $Header: /cvsroot/pgsql/src/backend/access/transam/Makefile,v 1.7 1999/09/27 15:47:37 vadim Exp $
7+
# $Header: /cvsroot/pgsql/src/backend/access/transam/Makefile,v 1.8 1999/10/24 20:42:27 tgl Exp $
88
#
99
#-------------------------------------------------------------------------
1010

@@ -26,6 +26,10 @@ depend dep:
2626
clean:
2727
rm -f SUBSYS.o$(OBJS)
2828

29+
# ensure that version checks in xlog.c get recompiled when config.h or
30+
# catversion.h changes, even if "make depend" hasn't been done.
31+
xlog.o: xlog.c$(SRCDIR)/include/config.h$(SRCDIR)/include/catalog/catversion.h
32+
2933
ifeq (depend,$(wildcard depend))
3034
include depend
3135
endif

‎src/backend/access/transam/xlog.c

Lines changed: 29 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,25 @@
1+
/*-------------------------------------------------------------------------
2+
*
3+
* xlog.c
4+
*
5+
*
6+
* Copyright (c) 1994, Regents of the University of California
7+
*
8+
* $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.6 1999/10/24 20:42:27 tgl Exp $
9+
*
10+
*-------------------------------------------------------------------------
11+
*/
112
#include<fcntl.h>
213
#include<unistd.h>
314
#include<errno.h>
415
#include<sys/stat.h>
516
#include<sys/time.h>
617

718
#include"postgres.h"
19+
820
#include"access/xlog.h"
921
#include"access/xact.h"
22+
#include"catalog/catversion.h"
1023
#include"storage/sinval.h"
1124
#include"storage/proc.h"
1225
#include"storage/spin.h"
@@ -99,12 +112,15 @@ typedef struct ControlFileData
99112
DBStatestate;/* */
100113

101114
/*
102-
*following data used to make sure thatconfigurations for this DB
103-
*do not conflictwith the backend
115+
*this dataisused to make sure thatconfiguration of this DB
116+
*is compatiblewith the current backend
104117
*/
105118
uint32blcksz;/* block size for this DB */
106-
uint32relseg_size;/* segmented file's block number */
107-
/* MORE DATA FOLLOWS AT THE END OF THIS STRUCTURE
119+
uint32relseg_size;/* blocks per segment of large relation */
120+
uint32catalog_version_no;/* internal version number */
121+
122+
/*
123+
* MORE DATA FOLLOWS AT THE END OF THIS STRUCTURE
108124
* - locations of data dirs
109125
*/
110126
}ControlFileData;
@@ -1171,6 +1187,7 @@ BootStrapXLOG()
11711187
ControlFile->state=DB_SHUTDOWNED;
11721188
ControlFile->blcksz=BLCKSZ;
11731189
ControlFile->relseg_size=RELSEG_SIZE;
1190+
ControlFile->catalog_version_no=CATALOG_VERSION_NO;
11741191

11751192
if (write(fd,buffer,BLCKSZ)!=BLCKSZ)
11761193
elog(STOP,"BootStrapXLOG failed to write control file: %d",errno);
@@ -1179,9 +1196,6 @@ BootStrapXLOG()
11791196
elog(STOP,"BootStrapXLOG failed to fsync control file: %d",errno);
11801197

11811198
close(fd);
1182-
1183-
return;
1184-
11851199
}
11861200

11871201
staticchar*
@@ -1258,11 +1272,16 @@ StartupXLOG()
12581272
!XRecOffIsValid(ControlFile->checkPoint.xrecoff))
12591273
elog(STOP,"Control file context is broken");
12601274

1275+
/* Check for incompatible database */
12611276
if (ControlFile->blcksz!=BLCKSZ)
1262-
elog(STOP,"database was initializedin BLCKSZ(%d), butthe backend was compiledin BLCKSZ(%d)",ControlFile->blcksz,BLCKSZ);
1263-
1277+
elog(STOP,"database was initializedwith BLCKSZ %d,\n\tbutthe backend was compiledwith BLCKSZ %d.\n\tlooks like you need to initdb.",
1278+
ControlFile->blcksz,BLCKSZ);
12641279
if (ControlFile->relseg_size!=RELSEG_SIZE)
1265-
elog(STOP,"database was initialized in RELSEG_SIZE(%d), but the backend was compiled in RELSEG_SIZE(%d)",ControlFile->relseg_size,RELSEG_SIZE);
1280+
elog(STOP,"database was initialized with RELSEG_SIZE %d,\n\tbut the backend was compiled with RELSEG_SIZE %d.\n\tlooks like you need to initdb.",
1281+
ControlFile->relseg_size,RELSEG_SIZE);
1282+
if (ControlFile->catalog_version_no!=CATALOG_VERSION_NO)
1283+
elog(STOP,"database was initialized with CATALOG_VERSION_NO %d,\n\tbut the backend was compiled with CATALOG_VERSION_NO %d.\n\tlooks like you need to initdb.",
1284+
ControlFile->catalog_version_no,CATALOG_VERSION_NO);
12661285

12671286
if (ControlFile->state==DB_SHUTDOWNED)
12681287
elog(LOG,"Data Base System was shutdowned at %s",

‎src/include/catalog/catversion.h

Lines changed: 56 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,56 @@
1+
/*-------------------------------------------------------------------------
2+
*
3+
* catversion.h
4+
* "Catalog version number" for Postgres.
5+
*
6+
* The catalog version number is used to flag incompatible changes in
7+
* the Postgres system catalogs. Whenever anyone changes the format of
8+
* a system catalog relation, or adds, deletes, or modifies standard
9+
* catalog entries in such a way that an updated backend wouldn't work
10+
* with an old database (or vice versa), the catalog version number
11+
* should be changed. The version number stored in pg_control by initdb
12+
* is checked against the version number compiled into the backend at
13+
* startup time, so that a backend can refuse to run in an incompatible
14+
* database.
15+
*
16+
* The point of this feature is to provide a finer grain of compatibility
17+
* checking than is possible from looking at the major version number
18+
* stored in PG_VERSION. It shouldn't matter to end users, but during
19+
* development cycles we usually make quite a few incompatible changes
20+
* to the contents of the system catalogs, and we don't want to bump the
21+
* major version number for each one. What we can do instead is bump
22+
* this internal version number. This should save some grief for
23+
* developers who might otherwise waste time tracking down "bugs" that
24+
* are really just code-vs-database incompatibilities.
25+
*
26+
* The rule for developers is: if you commit a change that requires
27+
* an initdb, you should update the catalog version number (as well as
28+
* notifying the pghackers mailing list, which has been the informal
29+
* practice for a long time).
30+
*
31+
* The catalog version number is placed here since modifying files in
32+
* include/catalog is the most common kind of initdb-forcing change.
33+
* But it could be used to protect any kind of incompatible change in
34+
* database contents or layout, such as altering tuple headers.
35+
*
36+
*
37+
* Copyright (c) 1994, Regents of the University of California
38+
*
39+
* $Id: catversion.h,v 1.1 1999/10/24 20:42:26 tgl Exp $
40+
*
41+
*-------------------------------------------------------------------------
42+
*/
43+
#ifndefCATVERSION_H
44+
#defineCATVERSION_H
45+
46+
/*
47+
* We could use anything we wanted for version numbers, but I recommend
48+
* following the "YYYYMMDDN" style often used for DNS zone serial numbers.
49+
* YYYYMMDD are the date of the change, and N is the number of the change
50+
* on that day. (Hopefully we'll never commit ten independent sets of
51+
* catalog changes on the same day...)
52+
*/
53+
54+
#defineCATALOG_VERSION_NO199910241
55+
56+
#endif

0 commit comments

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