</para>

</listitem>

</varlistentry>

<varlistentry>

<term>BASE_BACKUP <replaceable>options</><literal>;</><replaceable>label</></term>

<listitem>

<para>

Instructs the server to start streaming a base backup.

The system will automatically be put in backup mode with the label

specified in <replaceable>label</> before the backup is started, and

taken out of it when the backup is complete. The following options

are accepted:

<variablelist>

<varlistentry>

<term><literal>PROGRESS</></term>

<listitem>

<para>

Request information required to generate a progress report. This will

send back an approximate size in the header of each tablespace, which

can be used to calculate how far along the stream is done. This is

calculated by enumerating all the file sizes once before the transfer

is even started, and may as such have a negative impact on the

performance - in particular it may take longer before the first data

is streamed. Since the database files can change during the backup,

the size is only approximate and may both grow and shrink between

the time of approximation and the sending of the actual files.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

<para>

When the backup is started, the server will first send a header in

ordinary result set format, followed by one or more CopyResponse

results, one for PGDATA and one for each additional tablespace other

than <literal>pg_default</> and <literal>pg_global</>. The data in

the CopyResponse results will be a tar format (using ustar00

extensions) dump of the tablespace contents.

</para>

<para>

The header is an ordinary resultset with one row for each tablespace.

The fields in this row are:

<variablelist>

<varlistentry>

<term>spcoid</term>

<listitem>

<para>

The oid of the tablespace, or <literal>NULL</> if it's the base

directory.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term>spclocation</term>

<listitem>

<para>

The full path of the tablespace directory, or <literal>NULL</>

if it's the base directory.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term>size</term>

<listitem>

<para>

The approximate size of the tablespace, if progress report has

been requested; otherwise it's <literal>NULL</>.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

<para>

The tar archive for the data directory and each tablespace will contain

all files in the directories, regardless of whether they are

<productname>PostgreSQL</> files or other files added to the same

directory. The only excluded files are:

<itemizedlist spacing="compact" mark="bullet">

<listitem>

<para>

<filename>postmaster.pid</>

</para>

</listitem>

<listitem>

<para>

<filename>pg_xlog</> (including subdirectories)

</para>

</listitem>

</itemizedlist>

Owner, group and file mode are set if the underlying filesystem on

the server supports it.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

top_builddir = ../../..

include$(top_builddir)/src/Makefile.global

OBJS = walsender.o walreceiverfuncs.o walreceiver.o

OBJS = walsender.o walreceiverfuncs.o walreceiver.o basebackup.o

include$(top_srcdir)/src/backend/common.mk