How do you print the result of a PostgreSQL query in CSV or TSV format from the command line?

I'd like to execute a query from the shell (not in the interactive psql client) and have it print the CSV or TSV representation of the output to STDOUT. How do you do that with psql or one of the PostgreSQL command-line tools?

If you are using PostgreSQL 8.2 or newer, use this for CSV:

psql -c "COPY (<select query>) TO STDOUT WITH CSV"

and this of TSV, with proper NULLs:

psql -c "COPY (<select query>) TO STDOUT WITH NULL AS ''"

The CSV form will properly quote any fields that contain the double-quote character. See the PostgreSQL documentation of your specific version for more details and options for COPY.

Starting from Bohemian's answer, I found these flags useful:

psql my_database -U myuser -A -F , -X -t -f /path/to/query.sql -o /path/to/output.csv

• Unaligned output mode: -A
• Use comma as field delimiter: -F ,
• Do not read psqlrc: -X
• Tuples only (no header/footer): -t
• File containing SQL query: -f
• Output file: -o

EDITED: Using -F

Use commas via -F and use "unaligned table output mode" -A:

psql my_database -U myuser -A -F , -c "select * from mytable"

To specify a tsv use the delimiter '\t'

psql my_database -U myuser -F'\t' --no-align -f mysqlfile.sql -o outputfile.tsv

To specify a csv use the delimiter ','

psql my_database -U myuser -F',' --no-align -f mysqlfile.sql -o outputfile.csv

Also possible is the copy command which allows you to specify header, delimiters and quoting options

psql my_database -U my_user -c "copy (select a.id,b.id from my_table_a as a inner join my_table_b as b on b.id = a.id) to STDOUT"