Postgresql 中文操作指南

dropdb

dropdb – 删除 PostgreSQL 数据库

dropdb — remove a PostgreSQL database

Synopsis

dropdb [ connection-option …​] [ option …​] dbname

dropdb [connection-option…​] [option…​] dbname

Description

dropdb 销毁现有的 PostgreSQL 数据库。执行此命令的用户必须是数据库超级用户或数据库所有者。

dropdb destroys an existing PostgreSQL database. The user who executes this command must be a database superuser or the owner of the database.

dropdb 是封装了 SQL 命令 DROP DATABASE 的一个包装器。通过此实用工具删除数据库和通过访问服务器的其他方法删除数据库之间没有实质性差异。

dropdb is a wrapper around the SQL command DROP DATABASE. There is no effective difference between dropping databases via this utility and via other methods for accessing the server.

Options

dropdb 接受以下命令行参数：

dropdb accepts the following command-line arguments:

  • dbname

    • Specifies the name of the database to be removed.

  • -e_—​echo_

    • Echo the commands that 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 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 dropdb command line arguments, and exit.

dropdb 还接受以下用于连接参数的命令行参数：

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 dropdb to prompt for a password before connecting to a database.

    • This option is never essential, since dropdb will automatically prompt for a password if the server demands password authentication. However, 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

  • PGHOST_PGPORT_PGUSER

    • Default connection parameters

  • PG_COLOR

    • Specifies whether to use color in diagnostic messages. Possible values are always, auto and never.

此实用程序与大多数其他 PostgreSQL 实用程序一样，还使用 libpq 支持的环境变量（请参阅 Section 34.15 ）。

This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see Section 34.15).

Diagnostics

如果出现困难，请参阅 DROP DATABASE 和 psql 以讨论潜在问题和错误消息。数据库服务器必须在目标主机上运行。此外，libpq 前端库使用的任何默认连接设置和环境变量都将适用。

In case of difficulty, see DROP DATABASE and psql 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

要在默认数据库服务器上摧毁数据库 demo ：

To destroy the database demo on the default database server:

$ dropdb demo

要使用主机 eden 和端口 5000 上的服务器、使用验证和查看基础命令来摧毁数据库 demo ：

To destroy the database demo using the server on host eden, port 5000, with verification and a peek at the underlying command:

$ 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

createdb, DROP DATABASE