Name
gzip_uncompress,
gz_compress_file,
gz_uncompress_file,
unzip_file,
unzip_list,
xz_file_open,
bz2_file_open
— compress, decompress and read compressed files
Synopsis
any gzip_uncompress(
|
in input any); |
integer gz_compress_file(
|
in source_file varchar, |
| |
in target_file varchar); |
integer gz_uncompress_file(
|
in source_file varchar, |
| |
in target_file varchar); |
unzip_file(
|
in zip_archive varchar, |
| |
in entry_name varchar, |
| |
in target_file varchar); |
any unzip_list(
|
in zip_archive varchar); |
any xz_file_open(
|
in file varchar); |
any bz2_file_open(
|
in file varchar); |
Description
gzip_uncompress decompresses a gzip-compressed
string or string_output in memory and returns
the plaintext as a new string. It is the in-memory counterpart of
gz_uncompress.
gz_compress_file reads
source_file and writes a gzip-compressed copy to
target_file.
gz_uncompress_file reverses the operation, expanding
a .gz file. Both return a non-zero integer status on
success and raise an SQL error on I/O or compression failure. DBA
privileges are required.
unzip_file extracts the entry named
entry_name from a ZIP archive. With three arguments
the entry is written to target_file; with two
arguments the decompressed bytes are returned as a string.
unzip_list returns a vector describing every entry in
the archive (name, uncompressed size, compressed size, modification
timestamp).
xz_file_open opens an XZ/LZMA-compressed file for
streaming reads, returning a file-descriptor handle suitable for use with
the standard file_* reading BIFs.
bz2_file_open performs the same role for
bzip2-compressed files. Both expose the decompressed bytes through an
ordinary file-descriptor interface and are particularly useful for
processing large compressed datasets without materialising the whole
content in memory.