lt_dropdb

lt_dropdb — remove a LightDB database

Synopsis

lt_dropdb [connection-option...] [option...] dbname

Description

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.

Options

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.

Environment

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).

Diagnostics

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.

Examples

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;

See Also

createdb, DROP DATABASE