1 <!-- doc/src/sgml/pgupgrade.sgml -->
3 <sect1 id="pgupgrade" xreflabel="pg_upgrade">
4 <title>pg_upgrade</title>
6 <indexterm zone="pgupgrade">
7 <primary>pg_upgrade</primary>
11 <application>pg_upgrade</> (formerly called <application>pg_migrator</>) allows data
12 stored in <productname>PostgreSQL</> data files to be upgraded to a later <productname>PostgreSQL</>
13 major version without the data dump/reload typically required for
14 major version upgrades, e.g. from 8.4.7 to the current major release
15 of <productname>PostgreSQL</>. It is not required for minor version upgrades, e.g. from
20 Major PostgreSQL releases regularly add new features that often
21 change the layout of the system tables, but the internal data storage
22 format rarely changes. <application>pg_upgrade</> uses this fact
23 to perform rapid upgrades by creating new system tables and simply
24 reusing the old user data files. If a future major release ever
25 changes the data storage format in a way that makes the old data
26 format unreadable, <application>pg_upgrade</> will not be usable
27 for such upgrades. (The community will attempt to avoid such
32 <application>pg_upgrade</> does its best to
33 make sure the old and new clusters are binary-compatible, e.g. by
34 checking for compatible compile-time settings, including 32/64-bit
35 binaries. It is important that
36 any external modules are also binary compatible, though this cannot
37 be checked by <application>pg_upgrade</>.
41 <title>Supported Versions</title>
44 pg_upgrade supports upgrades from 8.3.X and later to the current
45 major release of <productname>PostgreSQL</>, including snapshot and alpha releases.
52 <title><application>pg_upgrade</> Options</title>
55 <application>pg_upgrade</application> accepts the following command-line arguments:
60 <term><option>-b</option> <replaceable>old_bindir</></term>
61 <term><option>--old-bindir=</option><replaceable>old_bindir</></term>
62 <listitem><para>the old cluster executable directory;
63 environment variable <envar>OLDBINDIR</></para></listitem>
67 <term><option>-B</option> <replaceable>new_bindir</></term>
68 <term><option>--new-bindir=</option><replaceable>new_bindir</></term>
69 <listitem><para>the new cluster executable directory;
70 environment variable <envar>NEWBINDIR</></para></listitem>
74 <term><option>-c</option></term>
75 <term><option>--check</option></term>
76 <listitem><para>check clusters only, don't change any data</para></listitem>
80 <term><option>-d</option> <replaceable>old_datadir</></term>
81 <term><option>--old-datadir=</option><replaceable>old_datadir</></term>
82 <listitem><para>the old cluster data directory; environment
83 variable <envar>OLDDATADIR</></para></listitem>
87 <term><option>-D</option> <replaceable>new_datadir</></term>
88 <term><option>--new-datadir=</option><replaceable>new_datadir</></term>
89 <listitem><para>the new cluster data directory; environment
90 variable <envar>NEWDATADIR</></para></listitem>
94 <term><option>-g</option></term>
95 <term><option>--debug</option></term>
96 <listitem><para>enable debugging</para></listitem>
100 <term><option>-G</option> <replaceable>debug_filename</></term>
101 <term><option>--debugfile=</option><replaceable>debug_filename</></term>
102 <listitem><para>output debugging activity to file</para></listitem>
106 <term><option>-k</option></term>
107 <term><option>--link</option></term>
108 <listitem><para>use hard links instead of copying files to the new cluster</para></listitem>
112 <term><option>-l</option> <replaceable>log_filename</></term>
113 <term><option>--logfile=</option><replaceable>log_filename</></term>
114 <listitem><para>log session activity to file</para></listitem>
118 <term><option>-p</option> <replaceable>old_port_number</></term>
119 <term><option>--old-port=</option><replaceable>old_portnum</></term>
120 <listitem><para>the old cluster port number; environment
121 variable <envar>PGPORT</></para></listitem>
125 <term><option>-P</option> <replaceable>new_port_number</></term>
126 <term><option>--new-port=</option><replaceable>new_portnum</></term>
127 <listitem><para>the new cluster port number; environment
128 variable <envar>PGPORT</></para></listitem>
132 <term><option>-u</option> <replaceable>user_name</></term>
133 <term><option>--user=</option><replaceable>user_name</></term>
134 <listitem><para>cluster's super user name; environment
135 variable <envar>PGUSER</></para></listitem>
139 <term><option>-v</option></term>
140 <term><option>--verbose</option></term>
141 <listitem><para>enable verbose output</para></listitem>
145 <term><option>-V</option></term>
146 <term><option>--version</option></term>
147 <listitem><para>display version information, then exit</para></listitem>
151 <term><option>-?</option></term>
152 <term><option>-h</option></term>
153 <term><option>--help</option></term>
154 <listitem><para>show help, then exit</para></listitem>
163 <title>Upgrade Steps</title>
166 <step performance="optional">
167 <title>Optionally move the old cluster</title>
170 If you are using a version-specific installation directory, e.g.
171 <filename>/opt/PostgreSQL/8.4</>, you do not need to move the old cluster. The
172 one-click installers all use version-specific installation directories.
176 If your installation directory is not version-specific, e.g.
177 <filename>/usr/local/pgsql</>, it is necessary to move the current PostgreSQL install
178 directory so it does not interfere with the new <productname>PostgreSQL</> installation.
179 Once the current <productname>PostgreSQL</> server is shut down, it is safe to rename the
180 PostgreSQL installation directory; assuming the old directory is
181 <filename>/usr/local/pgsql</>, you can do:
184 mv /usr/local/pgsql /usr/local/pgsql.old
186 to rename the directory.
191 <title>For source installs, build the new version</title>
194 Build the new PostgreSQL source with <command>configure</> flags that are compatible
195 with the old cluster. <application>pg_upgrade</> will check <command>pg_controldata</> to make
196 sure all settings are compatible before starting the upgrade.
201 <title>Install the new PostgreSQL binaries</title>
204 Install the new server's binaries and support files. You can use the
205 same port numbers for both clusters, typically 5432, because the old and
206 new clusters will not be running at the same time.
210 For source installs, if you wish to install the new server in a custom
211 location, use the <literal>prefix</literal> variable:
214 gmake prefix=/usr/local/pgsql.new install
220 <title>Install pg_upgrade and pg_upgrade_support</title>
223 Install the <application>pg_upgrade</> binary and
224 <application>pg_upgrade_support</> library in the new PostgreSQL cluster.
229 <title>Initialize the new PostgreSQL cluster</title>
232 Initialize the new cluster using <command>initdb</command>.
233 Again, use compatible <command>initdb</command>
234 flags that match the old cluster. Many
235 prebuilt installers do this step automatically. There is no need to
236 start the new cluster.
241 <title>Install custom shared object files</title>
244 Install any custom shared object files (or DLLs) used by the old cluster
245 into the new cluster, e.g. <filename>pgcrypto.so</filename>, whether they are from <filename>contrib</filename>
246 or some other source. Do not install the schema definitions, e.g.
247 <filename>pgcrypto.sql</>, because these will be upgraded from the old cluster.
252 <title>Adjust authentication</title>
255 <command>pg_upgrade</> will connect to the old and new servers several times,
256 so you might want to set authentication to <literal>trust</> in
257 <filename>pg_hba.conf</>, or if using <literal>md5</> authentication,
258 use a <filename>~/.pgpass</> file (see <xref linkend="libpq-pgpass">)
259 to avoid being prompted repeatedly for a password. Also make sure
260 pg_upgrade is the only program that can connect to the clusters.
265 <title>Stop both servers</title>
268 Make sure both database servers are stopped using, on Unix, e.g.:
271 pg_ctl -D /opt/PostgreSQL/8.4 stop
272 pg_ctl -D /opt/PostgreSQL/9.0 stop
275 or on Windows, using the proper service names:
278 NET STOP postgresql-8.4
279 NET STOP postgresql-9.0
285 NET STOP pgsql-8.3 (<productname>PostgreSQL</> 8.3 and older used a different service name)
291 <title>Run <application>pg_upgrade</></title>
294 Always run the <application>pg_upgrade</> binary of the new server, not the old one.
295 <application>pg_upgrade</> requires the specification of the old and new cluster's
296 data and executable (<filename>bin</>) directories. You can also specify
297 user and port values, and whether you want the data linked instead of
298 copied (the default).
302 If you use link mode, the upgrade will be much faster (no file
303 copying), but you will not be able to access your old cluster
304 once you start the new cluster after the upgrade. Link mode also
305 requires that the old and new cluster data directories be in the
306 same file system. See <literal>pg_upgrade --help</> for a full
311 For Windows users, you must be logged into an administrative account, and
312 then start a shell as the <literal>postgres</> user and set the proper path:
315 RUNAS /USER:postgres "CMD.EXE"
316 SET PATH=%PATH%;C:\Program Files\PostgreSQL\9.0\bin;
319 and then run <application>pg_upgrade</> with quoted directories, e.g.:
323 --old-datadir "C:/Program Files/PostgreSQL/8.4/data"
324 --new-datadir "C:/Program Files/PostgreSQL/9.0/data"
325 --old-bindir "C:/Program Files/PostgreSQL/8.4/bin"
326 --new-bindir "C:/Program Files/PostgreSQL/9.0/bin"
329 Once started, <command>pg_upgrade</> will verify the two clusters are compatible
330 and then do the upgrade. You can use <command>pg_upgrade --check</>
331 to perform only the checks, even if the old server is still
332 running. <command>pg_upgrade --check</> will also outline any
333 manual adjustments you will need to make after the upgrade.
334 <command>pg_upgrade</> requires write permission in the current directory.
338 Obviously, no one should be accessing the clusters during the upgrade.
342 If an error occurs while restoring the database schema, <command>pg_upgrade</> will
343 exit and you will have to revert to the old cluster as outlined in <xref linkend="pgupgrade-step-revert">
344 below. To try <command>pg_upgrade</command> again, you will need to modify the old
345 cluster so the pg_upgrade schema restore succeeds. If the problem is a
346 contrib module, you might need to uninstall the contrib module from
347 the old cluster and install it in the new cluster after the upgrade,
348 assuming the module is not being used to store user data.
353 <title>Restore <filename>pg_hba.conf</></title>
356 If you modified <filename>pg_hba.conf</> to use <literal>trust</>,
357 restore its original authentication settings.
362 <title>Post-Upgrade processing</title>
365 If any post-upgrade processing is required, pg_upgrade will issue
366 warnings as it completes. It will also generate script files that must
367 be run by the administrator. The script files will connect to each
368 database that needs post-upgrade processing. Each script should be
372 psql --username postgres --file script.sql postgres
375 The scripts can be run in any order and can be deleted once they have
381 In general it is unsafe to access tables referenced in rebuild scripts
382 until the rebuild scripts have run to completion; doing so could yield
383 incorrect results or poor performance. Tables not referenced in rebuild
384 scripts can be accessed immediately.
390 <title>Statistics</title>
393 Because optimizer statistics are not transferred by <command>pg_upgrade</>, you will
394 be instructed to run a command to regenerate that information at the end
400 <title>Delete old cluster</title>
403 Once you are satisfied with the upgrade, you can delete the old
404 cluster's data directories by running the script mentioned when
405 <command>pg_upgrade</command> completes. You can also delete the
406 old installation directories
407 (e.g. <filename>bin</>, <filename>share</>).
411 <step id="pgupgrade-step-revert" performance="optional">
412 <title>Reverting to old cluster</title>
415 If, after running <command>pg_upgrade</command>, you wish to revert to the old cluster,
416 there are several options:
421 If you ran <command>pg_upgrade</command>
422 with <option>--check</>, no modifications were made to the old
423 cluster and you can re-use it anytime.
429 If you ran <command>pg_upgrade</command>
430 with <option>--link</>, the data files are shared between the
431 old and new cluster. If you started the new cluster, the new
432 server has written to those shared files and it is unsafe to
440 ran <command>pg_upgrade</command> <emphasis>without</> <option>--link</>
441 or did not start the new server, the old cluster was not
442 modified except that an <literal>.old</> suffix was appended
443 to <filename>$PGDATA/global/pg_control</> and perhaps
444 tablespace directories. To reuse the old cluster, remove
445 the <filename>.old</> suffix
446 from <filename>$PGDATA/global/pg_control</>. and, if upgrading
447 to 8.4 or earlier, remove the tablespace directories created
448 by the upgrade and remove the <filename>.old</> suffix from
449 the tablespace directory names; then you can restart the old
461 <title>Limitations in Upgrading <emphasis>from</> PostgreSQL 8.3</title>
464 Upgrading from PostgreSQL 8.3 has additional restrictions not present
465 when upgrading from later PostgreSQL releases. For example,
466 pg_upgrade will not work for upgrading from 8.3 if a user column
471 a <type>tsquery</> data type
476 data type <type>name</> and is not the first column
483 You must drop any such columns and upgrade them manually.
487 pg_upgrade will require a table rebuild if:
491 a user column is of data type <type>tsvector</type>
498 pg_upgrade will require a reindex if:
502 an index is of type hash or GIN
507 an index uses <function>bpchar_pattern_ops</>
514 Also, the default datetime storage format changed to integer after
515 <productname>PostgreSQL</> 8.3. pg_upgrade will check that the datetime storage format
516 used by the old and new clusters match. Make sure your new cluster is
517 built with the configure flag <option>--disable-integer-datetimes</>.
521 For Windows users, note that due to different integer datetimes settings
522 used by the one-click installer and the MSI installer, it is only
523 possible to upgrade from version 8.3 of the one-click distribution to
524 version 8.4 or later of the one-click distribution. It is not
525 possible to upgrade from the MSI installer to the one-click installer.
534 <application>pg_upgrade</> does not support upgrading of databases
535 containing these <type>reg*</> OID-referencing system data types:
536 <type>regproc</>, <type>regprocedure</>, <type>regoper</>,
537 <type>regoperator</>, <type>regclass</>, <type>regconfig</>, and
538 <type>regdictionary</>. (<type>regtype</> can be upgraded.)
542 All failure, rebuild, and reindex cases will be reported by
543 <application>pg_upgrade</> if they affect your installation;
544 post-upgrade scripts to rebuild tables and indexes will be
545 generated automatically.
549 For deployment testing, create a schema-only copy of the old cluster,
550 insert dummy data, and upgrade that.
554 If you want to use link mode and you don't want your old cluster
555 to be modified when the new cluster is started, make a copy of the
556 old cluster and upgrade that with link mode. To make a valid copy
557 of the old cluster, use <command>rsync</> to create a dirty
558 copy of the old cluster while the server is running, then shut down
559 the old server and run <command>rsync</> again to update the copy with any
560 changes to make it consistent.