I need to export a big table to csv file and compress it.
I can export it using COPY command from postgres like -
COPY foo_table to \'/tmp/foo_table.csv
Expanding a bit on @Joey's answer, below adds support for a couple more features available in the manual.
psql -c "COPY \"Foo_table\" (column1, column2) TO stdout DELIMITER ',' CSV HEADER" \
| gzip > foo_table.csv.gz
If you have capital letters in your table name (woe be onto you), you need the \"
before and after the table name.
The second thing I've added is column listing.
Also note from the docs:
This operation is not as efficient as the SQL COPY command because all data must pass through the client/server connection. For large amounts of data the SQL command might be preferable.