Is it possible to export a table to csv, but to append multiple selections to the same file?
I would like to export (for instance):
SELECT * FROM TABLE WHERE a > 5
Then, later:
SELECT * FROM TABLE WHERE b > 2
This must go to the same file.
Thanks in advance!
The only way that I know of to do this is from the command-line, redirecting output.
psql -d dbname -t -A -F"," -c "SELECT * FROM TABLE WHERE a > 5" >> output.csv
then later
psql -d dbname -t -A -F"," -c "SELECT * FROM TABLE WHERE b > 2" >> output.csv
You can look up the command line options here.
Use \o <filename> to output to a file. All your SELECT statements after using \o will be appended to <file> until you set \o to something else.
Using \o in combination with \copy to STDOUT seems to work. For example:
db=> \o /tmp/test.csv
db=> \copy (select 'foo','bar') to STDOUT with CSV;
db=> \copy (select 'foo','bar') to STDOUT with CSV;
db=> \q
$ cat /tmp/test.csv
foo,bar
foo,bar
