adminpack 提供了許多支援性質的函數,pgAdmin 和其他管理工具可以用來提供其他功能,例如伺服器日誌檔案的遠程管理。預設情況下,僅超級使用者可以使用所有的這些函數,但使用 GRANT 指令可以允許其他使用者使用它們。
Table F.1 中列出的函數提供了對伺服器的主機上檔案的寫入功能。 (另請參見 Table 9.99 中提供唯讀的功能。)只能存取資料庫叢集目錄中的檔案,除非使用者是超級使用者或具有 pg_read_server_files 或 pg_write_server_files 個角色(視情況而定) ,而相對路徑及絕對路徑都是允許的。
adminpack
Functionspg_file_write
writes the specified data
into the file named by filename
. If append
is false, the file must not already exist. If append
is true, the file can already exist, and will be appended to if so. Returns the number of bytes written.
pg_file_sync fsyncs filename 所指定檔案或目錄。 失敗時會拋出錯誤(例如,指定的路徑不存在)。 請注意,data_sync_retry 對此函數沒有影響,因此即使更新資料庫檔案失敗也不會引發 PANIC 層級的錯誤。
pg_file_rename
renames a file. If archivename
is omitted or NULL, it simply renames oldname
to newname
(which must not already exist). If archivename
is provided, it first renames newname
to archivename
(which must not already exist), and then renames oldname
to newname
. In event of failure of the second rename step, it will try to rename archivename
back to newname
before reporting the error. Returns true on success, false if the source file(s) are not present or not writable; other cases throw errors.
pg_file_unlink
removes the specified file. Returns true on success, false if the specified file is not present or the unlink()
call fails; other cases throw errors.
pg_logdir_ls 回傳 log_directory 目錄中所有日誌檔案的開始時間戳記和路徑名稱。 log_filename 參數必須有其預設設定 (postgresql-%Y-%m-%d_%H%M%S.log) 才能使用此功能。
Function
Description
pg_catalog.pg_file_write
( filename
text
, data
text
, append
boolean
) → bigint
Writes, or appends to, a text file.
pg_catalog.pg_file_sync
( filename
text
) → void
Flushes a file or directory to disk.
pg_catalog.pg_file_rename
( oldname
text
, newname
text
[, archivename
text
] ) → boolean
Renames a file.
pg_catalog.pg_file_unlink
( filename
text
) → boolean
Removes a file.
pg_catalog.pg_logdir_ls
() → setof record
Lists the log files in the log_directory
directory.