pg_recvlogical — control PostgreSQL™ logical decoding streams
pg_recvlogical
[option
...]
pg_recvlogical controls logical decoding replication slots and streams data from such replication slots.
It creates a replication-mode connection, so it is subject to the same constraints as pg_receivexlog(1), plus those for logical replication (see Chapter 46, Logical Decoding).
At least one of the following options must be specified to select an action:
--create-slot
Create a new logical replication slot with the name specified by
--slot
, using the output plugin specified by
--plugin
, for the database specified
by --dbname
.
--drop-slot
Drop the replication slot with the name specified
by --slot
, then exit.
--start
Begin streaming changes from the logical replication slot specified
by --slot
, continuing until terminated by a
signal. If the server side change stream ends with a server shutdown
or disconnect, retry in a loop unless
--no-loop
is specified.
The stream format is determined by the output plugin specified when the slot was created.
The connection must be to the same database used to create the slot.
--create-slot
and --start
can be
specified together. --drop-slot
cannot be combined with
another action.
The following command-line options control the location and format of the output and other replication behavior:
-f filename
, --file=filename
Write received and decoded transaction data into this
file. Use -
for stdout.
-F interval_seconds
, --fsync-interval=interval_seconds
Specifies how often pg_recvlogical should
issue fsync()
calls to ensure the output file is
safely flushed to disk.
The server will occasionally request the client to perform a flush and report the flush position to the server. This setting is in addition to that, to perform flushes more frequently.
Specifying an interval of 0
disables
issuing fsync()
calls altogether, while still
reporting progress to the server. In this case, data could be lost in
the event of a crash.
-I lsn
, --startpos=lsn
In --start
mode, start replication from the given
LSN. For details on the effect of this, see the documentation
in Chapter 46, Logical Decoding
and the section called “Streaming Replication Protocol”. Ignored in other modes.
-n
, --no-loop
When the connection to the server is lost, do not retry in a loop, just exit.
-o name
[=value
]
, --option=name
[=value
]
Pass the option name
to the output plugin with,
if specified, the option value value
. Which
options exist and their effects depends on the used output plugin.
-P plugin
, --plugin=plugin
When creating a slot, use the specified logical decoding output plugin. See Chapter 46, Logical Decoding. This option has no effect if the slot already exists.
-s interval_seconds
, --status-interval=interval_seconds
This option has the same effect as the option of the same name in pg_receivexlog(1). See the description there.
-S slot_name
, --slot=slot_name
In --start
mode, use the existing logical replication slot named
slot_name
. In --create-slot
mode, create the slot with this name. In --drop-slot
mode, delete the slot with this name.
-v
, --verbose
Enables verbose mode.
The following command-line options control the database connection parameters.
-d database
, --dbname=database
The database to connect to. See the description of the actions for what this means in detail. This can be a libpq connection string; see the section called “Connection Strings” for more information. Defaults to user name.
-h hostname-or-ip
, --host=hostname-or-ip
Specifies the host name of the machine on which the server is
running. If the value begins with a slash, it is used as the
directory for the Unix domain socket. The default is taken
from the PGHOST
environment variable, if set,
else a Unix domain socket connection is attempted.
-p port
, --port=port
Specifies the TCP port or local Unix domain socket file
extension on which the server is listening for connections.
Defaults to the PGPORT
environment variable, if
set, or a compiled-in default.
-U user
, --username=user
Username to connect as. Defaults to current operating system user name.
-w
, --no-password
Never issue a password prompt. If the server requires
password authentication and a password is not available by
other means such as a .pgpass
file, the
connection attempt will fail. This option can be useful in
batch jobs and scripts where no user is present to enter a
password.
-W
, --password
Force pg_recvlogical to prompt for a password before connecting to a database.
This option is never essential, since
pg_recvlogical will automatically prompt
for a password if the server demands password authentication.
However, pg_recvlogical will waste a
connection attempt finding out that the server wants a password.
In some cases it is worth typing -W
to avoid the extra
connection attempt.
The following additional options are available:
-V
, --version
Print the pg_recvlogical version and exit.
-?
, --help
Show help about pg_recvlogical command line arguments, and exit.
This utility, like most other PostgreSQL™ utilities, uses the environment variables supported by libpq (see the section called “Environment Variables”).