<indexterm>

<primary>pg_create_restore_point</primary>

</indexterm>

<indexterm>

<primary>pg_current_xlog_flush_location</primary>

</indexterm>

<indexterm>

<primary>pg_current_xlog_insert_location</primary>

</indexterm>

<entry><type>pg_lsn</type></entry>

<entry>Create a named point for performing restore (restricted to superusers)</entry>

</row>

<row>

<entry>

<literal><function>pg_current_xlog_flush_location()</function></literal>

</entry>

<entry><type>pg_lsn</type></entry>

<entry>Get current transaction log flush location</entry>

</row>

<row>

<entry>

<literal><function>pg_current_xlog_insert_location()</function></literal>

<function>pg_current_xlog_location</> displays the current transaction log write

location in the same format used by the above functions. Similarly,

<function>pg_current_xlog_insert_location</> displays the current transaction log

insertion point. The insertion point is the <quote>logical</> end

of the transaction log

at any instant, while the write location is the end of what has actually

been written out from the server's internal buffers. The write location

is the end of what can be examined from outside the server, and is usually

insertion point and <function>pg_current_xlog_flush_location</> displays the

current transaction log flush point. The insertion point is the <quote>logical</>

end of the transaction log at any instant, while the write location is the end of

what has actually been written out from the server's internal buffers and flush

location is the location guaranteed to be written to durable storage. The write

location is the end of what can be examined from outside the server, and is usually

what you want if you are interested in archiving partially-complete transaction log

files. The insertionpoint is made available primarily for server

files. The insertionand flush points are made available primarily for server

debugging purposes. These are both read-only operations and do not

require superuser permissions.

</para>

PG_RETURN_LSN(current_recptr);

}

pg_current_xlog_flush_location(PG_FUNCTION_ARGS)

{

XLogRecPtrcurrent_recptr;

if (RecoveryInProgress())

ereport(ERROR,

(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),

errmsg("recovery is in progress"),

errhint("WAL control functions cannot be executed during recovery.")));

current_recptr=GetFlushRecPtr();

PG_RETURN_LSN(current_recptr);

}

externDatumpg_create_restore_point(PG_FUNCTION_ARGS);

externDatumpg_current_xlog_location(PG_FUNCTION_ARGS);

externDatumpg_current_xlog_insert_location(PG_FUNCTION_ARGS);

externDatumpg_current_xlog_flush_location(PG_FUNCTION_ARGS);

externDatumpg_last_xlog_receive_location(PG_FUNCTION_ARGS);

externDatumpg_last_xlog_replay_location(PG_FUNCTION_ARGS);

externDatumpg_last_xact_replay_timestamp(PG_FUNCTION_ARGS);

DESCR("current xlog write location");

DATA(insert OID = 2852 ( pg_current_xlog_insert_locationPGNSP PGUID 12 1 0 0 0 f f f f t f v s 0 0 3220 "" _null_ _null_ _null_ _null_ _null_ pg_current_xlog_insert_location _null_ _null_ _null_ ));

DESCR("current xlog insert location");

DATA(insert OID = 3330 ( pg_current_xlog_flush_locationPGNSP PGUID 12 1 0 0 0 f f f f t f v s 0 0 3220 "" _null_ _null_ _null_ _null_ _null_ pg_current_xlog_flush_location _null_ _null_ _null_ ));

DESCR("current xlog flush location");

DATA(insert OID = 2850 ( pg_xlogfile_name_offsetPGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 2249 "3220" "{3220,25,23}" "{i,o,o}" "{wal_location,file_name,file_offset}" _null_ _null_ pg_xlogfile_name_offset _null_ _null_ _null_ ));

DESCR("xlog filename and byte offset, given an xlog location");

DATA(insert OID = 2851 ( pg_xlogfile_namePGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 25 "3220" _null_ _null_ _null_ _null_ _null_ pg_xlogfile_name _null_ _null_ _null_ ));