Is it possible to get a history of queries made in postgres

You can use like

\s 

it will fetch you all command history of the terminal, to export it to file using

\s filename

If you want to identify slow queries, than the method is to use log_min_duration_statement setting (in postgresql.conf or set per-database with ALTER DATABASE SET).

When you logged the data, you can then use grep or some specialized tools - like pgFouine or my own analyzer - which lacks proper docs, but despite this - runs quite well.

There's no history in the database itself, if you're using psql you can use "\s" to see your command history there.

You can get future queries or other types of operations into the log files by setting log_statement in the postgresql.conf file. What you probably want instead is log_min_duration_statement, which if you set it to 0 will log all queries and their durations in the logs. That can be helpful once your apps goes live, if you set that to a higher value you'll only see the long running queries which can be helpful for optimization (you can run EXPLAIN ANALYZE on the queries you find there to figure out why they're slow).

Another handy thing to know in this area is that if you run psql and tell it "\timing", it will show how long every statement after that takes. So if you have a sql file that looks like this:

\timing
select 1;

You can run it with the right flags and see each statement interleaved with how long it took. Here's how and what the result looks like:

$ psql -ef test.sql 
Timing is on.
select 1;
 ?column? 
----------
        1
(1 row)

Time: 1.196 ms

This is handy because you don't need to be database superuser to use it, unlike changing the config file, and it's easier to use if you're developing new code and want to test it out.

If The question is the see the history of queries executed in the Command line. Answer is

As per Postgresql 9.3, Try \? in your command line, you will find all possible commands, in that search for history,

  \s [FILE]              display history or save it to file

in your command line, try \s. This will list the history of queries, you have executed in the current session. you can also save to the file, as shown below.

hms=# \s /tmp/save_queries.sql
Wrote history to file ".//tmp/save_queries.sql".
hms=#