PSQL tips

Write at 2017 May 21 in notes docker development

I like psql a lot than a GUI, everything is just on your finger tips and every single time when I used it, I build up my memory which definetely help when inspecting/debuging Postgres in production.

Passing credential via env

Typing password everytime is painful. Using environment var is a better way because when pairing with a password manager I can fetch them from my terminal and have psql immediately login

export PGHOST=localhost
export PGUSER=username
export PGPASSWORD=password

It’s really useful when using in a headless manner such as in script or a cron where noone is there to type in a password.

If you have multiple postgres server, you can put a file in ~/.pgpass with these content

# follow this format
# hostname:port:database:username:password
localhost:*:*:postgres:postgres

Then later on simply do psql -h server and you’re in.

History

Want to see what did you run, use \s to see your history. If you want to save it some some file \s filename

Run command from file

\i filename

Timing

On Linux, we have the command time. Prefix it with command will let you know how long a thing take to run. Example

time curl https://hanami.run
curl https://hanami.run  0.02s user 0.01s system 3% cpu 0.833 total

We can do the same with psql using \timing. After you type that command, any SQL query will report it time at the end. If you no longer want time reporting, enter \timing again.

# \timing
Timing is on.
(@localhost:5432) 03:52:19
# select * from foo;
 id | name
----+------
  1 | john
  2 | jane
(2 rows)

Time: 2.740 ms

Want Email Forwarding For Your Domain? Check out hanami.