tests, it cannot guarantee that the database will not reach a state

in which the constraint condition is false (due to subsequent changes

of the other row(s) involved). This would cause a database dump and

database state is consistent with the constraint, due to rows not

being loaded in an order that will satisfy the constraint. If

possible, use <literal>UNIQUE</literal>, <literal>EXCLUDE</literal>,

If what you desire is a one-time check against other rows at row

insertion, rather than a continuously-maintained consistency

guarantee, a custom <link linkend="triggers">trigger</link> can be used

<application>pg_dump</application> does not reinstall triggers until after

</para>

</note>

function. <productname>PostgreSQL</productname> does not disallow

that, but it will not notice if there are rows in the table that now

violate the <literal>CHECK</literal> constraint. That would cause a

The recommended way to handle such a change is to drop the constraint

(using <command>ALTER TABLE</command>), adjust the function definition,

and re-add the constraint, thereby rechecking it against all table rows.

<application>pg_dump</application>. But that behavior is undesirable for a

configuration table; any data changes made by the user need to be

included in dumps, or the extension will behave differently after a dump

</para>

<indexterm>

<para>

Dump scripts generated by <application>pg_dump</application> automatically apply

<application>pg_dump</application> dump as quickly as possible, you need to

do a few extra things manually. (Note that these points apply while

<emphasis>restoring</emphasis> a dump, not while <emphasis>creating</emphasis> it.

attached to a function when <varname>check_function_bodies</varname> is on.

Therefore, checks whose results might be affected by GUC parameters

definitely should be skipped when <varname>check_function_bodies</varname> is

</para>

<para>

around</quote> since the original creation of the enum type). The slowdown is

usually insignificant; but if it matters, optimal performance can be

regained by dropping and recreating the enum type, or by dumping and

</para>

</refsect1>

function. <productname>PostgreSQL</productname> does not disallow that,

but it will not notice if there are stored values of the domain type that

now violate the <literal>CHECK</literal> constraint. That would cause a

handle such a change is to drop the constraint (using <command>ALTER

DOMAIN</command>), adjust the function definition, and re-add the

constraint, thereby rechecking it against stored data.

...</literal>). This will make restoration very slow; it is mainly

useful for making dumps that can be loaded into

non-<productname>PostgreSQL</productname> databases.

problematic <command>INSERT</command> to be lost, rather than the

entire table contents.

</para>

This option is relevant only when creating a data-only dump.

It instructs <application>pg_dump</application> to include commands

to temporarily disable triggers on the target tables while

integrity checks or other triggers on the tables that you

</para>

<para>

than <command>COPY</command>). This will make restoration very slow;

it is mainly useful for making dumps that can be loaded into

non-<productname>PostgreSQL</productname> databases.

problematic <command>INSERT</command> to be lost, rather than the

entire table contents. Note that the restore might fail altogether if

you have rearranged column order. The

target the root of the partitioning hierarchy that contains it, rather

than the partition itself. This causes the appropriate partition to

be re-determined for each row when the data is loaded. This may be

into the same partitions as they did on the original server. That

could happen, for example, if the partitioning column is of type text

and the two systems have different definitions of the collation used

with this option, because <application>pg_restore</application> will

not know exactly which partition(s) a given archive data item will

load data into. This could result in inefficiency due to lock

to foreign key constraints being set up before all the relevant data

is loaded.

</para>

Dump data as <command>INSERT</command> commands (rather than

<command>COPY</command>). Controls the maximum number of rows per

<command>INSERT</command> command. The value specified must be a

rows that are part of the problematic <command>INSERT</command> to be

lost, rather than the entire table contents.

</para>

This option is relevant only when creating a data-only dump.

It instructs <application>pg_dumpall</application> to include commands

to temporarily disable triggers on the target tables while

integrity checks or other triggers on the tables that you

</para>

<para>

target the root of the partitioning hierarchy that contains it, rather

than the partition itself. This causes the appropriate partition to

be re-determined for each row when the data is loaded. This may be

into the same partitions as they did on the original server. That

could happen, for example, if the partitioning column is of type text

and the two systems have different definitions of the collation used

Dump data as <command>INSERT</command> commands (rather than

<command>COPY</command>). Controls the maximum number of rows per

<command>INSERT</command> command. The value specified must be a

rows that are part of the problematic <command>INSERT</command> to be

lost, rather than the entire table contents.

</para>

</para>

<para>

<screen>

<prompt>$</prompt> <userinput>psql -f db.out postgres</userinput>

</screen>

After running this command, it should be possible to start the server,

but bear in mind that the database might contain inconsistent data due to

partially-committed transactions. You should immediately dump your data,

inconsistencies and repair as needed.

</para>

discussed below. If you are not able to determine correct values for all

these fields, <option>-f</option> can still be used, but

the recovered database must be treated with even more suspicion than

execute any data-modifying operations in the database before you dump,

as any such action is likely to make the corruption worse.

</para>

This option is relevant only when performing a data-only restore.

It instructs <application>pg_restore</application> to execute commands

to temporarily disable triggers on the target tables while

integrity checks or other triggers on the tables that you

</para>

<para>

</para>

<para>

<screen>

<prompt>$</prompt> <userinput>createdb -T template0 newdb</userinput>

<para>

<application>pg_upgrade</application> (formerly called <application>pg_migrator</application>) allows data

stored in <productname>PostgreSQL</productname> data files to be upgraded to a later <productname>PostgreSQL</productname>

major version upgrades, e.g., from 9.5.8 to 9.6.4 or from 10.7 to 11.2.

It is not required for minor version upgrades, e.g., from 9.6.2 to 9.6.3

or from 10.1 to 10.2.

<para>

The <option>--jobs</option> option allows multiple CPU cores to be used

in parallel; a good place to start is the maximum of the number of

CPU cores and tablespaces. This option can dramatically reduce the

time to upgrade a multi-database server running on a multiprocessor

For <emphasis>major</emphasis> releases of <productname>PostgreSQL</productname>, the

internal data storage format is subject to change, thus complicating

upgrades. The traditional method for moving data to a new major version

faster method is <xref linkend="pgupgrade"/>. Replication methods are

also available, as discussed below.

(If you are using a pre-packaged version

<para>

One upgrade method is to dump data from one major version of

this, you must use a <emphasis>logical</emphasis> backup tool like

<application>pg_dumpall</application>; file system

level backup methods will not work. (There are checks in place that prevent

explicitly when creating <type>tsvector</type> values inside triggers,

so that the column's contents will not be affected by changes to

<varname>default_text_search_config</varname>. Failure to do this is likely to

</para>

</sect2>