Hi, On Thu, Nov 7, 2024 at 8:16 AM Joel Jacobson <j...@compiler.org> wrote: > > Hi hackers, > > Thread [1] renamed, since the format name has now been changed from 'raw' to > 'single', as suggested by Andrew Dunstan and Jacob Champion. > > [1] https://postgr.es/m/c12516b1-77dc-4ad3-94a7-88527360a...@app.fastmail.com > > Recap: This is about adding support to import/export text-based formats such > as > JSONL, or any unstructured text file, where wanting to import each line "as > is" > into a single column, or wanting to export a single column to a text file. > > Example importing the meson-logs/testlog.json file Meson generates > when building PostgreSQL, which is in JSONL format: > > # create table meson_log (log_line jsonb); > # \copy meson_log from meson-logs/testlog.json (format single); > COPY 306 > # select log_line->'name' name, log_line->'result' result from meson_log > limit 3; > name | result > -----------------------------------------+-------- > "postgresql:setup / tmp_install" | "OK" > "postgresql:setup / install_test_files" | "OK" > "postgresql:setup / initdb_cache" | "OK" > (3 rows) > > Changes since v16: > > * EOL handling now works the same as for 'text' and 'csv'. > In v16, we supported multi-byte delimiters to allow specifying > e.g. Windows EOL (\r\n), but this seemed unnecessary, if we just do what we do > for text/csv, that is, to auto-detect the EOL for COPY FROM, and use > the OS default EOL for COPY TO. > The DELIMITER option is therefore invalid for the 'single' format. > This is the biggest change in the code, between v16 and v18. > CopyReadLineRawText() has been renamed to CopyReadLineSingleText(), > and changed accordingly.
In earlier versions, we supported loading the whole file into a single tuple. Is there any reason that it doesn't support it in v18? I think if it's useful we can improve it in a separate patch. > > * A final EOL is now emitted to the last record in COPY TO. > So now it works just like 'text' and 'csv'. > +1 > * HEADER [ boolean | MATCH ] now supported > This is now again supported, as previously suggested by Daniel Verite, > possible thanks to the EOL handling. It makes sense to support it. Regards, -- Masahiko Sawada Amazon Web Services: https://aws.amazon.com
