lt_dropdb — remove a LightDB database
lt_dropdb
[connection-option
...] [option
...] dbname
lt_dropdb destroys an existing LightDB database. The user who executes this command must be a database superuser or the owner of the database.
lt_dropdb is a wrapper for the dropdb command. It is equivalent to removing a database using the dropdb command directly. However, in a distributed environment (Canopy), it automatically removes the database on all nodes, and these databases together form a distributed cluster.
Note: Canopy is related to databases. This tool only checks the deployment status of Canopy in the LightDB database, retrieves the list of Canopy nodes from the LightDB database, and then creates a database with the same name on each node.
lt_dropdb accepts the following command-line arguments:
dbname
Specifies the name of the database to be removed.
-e
--echo
Echo the commands that lt_dropdb generates and sends to the server.
-f
--force
Attempt to terminate all existing connections to the target database before dropping it. See DROP DATABASE for more information on this option.
-i
--interactive
Issues a verification prompt before doing anything destructive.
-V
--version
Print the lt_dropdb version and exit.
--if-exists
Do not throw an error if the database does not exist. A notice is issued in this case.
-?
--help
Show help about lt_dropdb command line arguments, and exit.
lt_dropdb also accepts the following command-line arguments for connection parameters:
-h host
--host=host
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.
-p port
--port=port
Specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections.
-U username
--username=username
User name to connect as.
-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 lt_dropdb to prompt for a password before connecting to a database.
This option is never essential, since
lt_dropdb will automatically prompt
for a password if the server demands password authentication.
However, lt_dropdb 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.
--maintenance-db=dbname
Specifies the name of the database to connect to in order to drop the
target database. If not specified, the postgres
database will be used; if that does not exist (or is the database
being dropped), template1
will be used.
This can be a connection
string. If so, connection string parameters will override any
conflicting command line options.
LTHOST
LTPORT
LTUSER
Default connection parameters
LT_COLOR
Specifies whether to use color in diagnostic messages. Possible values
are always
, auto
and
never
.
This utility, like most other LightDB utilities, also uses the environment variables supported by libpq (see Section 32.14).
In case of difficulty, see DROP DATABASE and ltsql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any default connection settings and environment variables used by the libpq front-end library will apply.
To destroy the database demo
on the default
database server:
$
lt_dropdb demo
To destroy the database demo
using the
server on host eden
, port 5000, with verification and a peek
at the underlying command:
$
lt_dropdb -p 5000 -h eden -i -e demo
Database "demo" will be permanently deleted. Are you sure? (y/n)
y
DROP DATABASE demo;