I am using the Ruby on Rails 3.1 pre version. I like to use PostgreSQL, but the problem is installing the pg gem. It gives me the following error: $ gem install pg Building native extensions. This could take a while… ERROR: Error installing pg: ERROR: Failed to build gem native extension. /home/u/.rvm/rubies/ruby-1.9.2-p0/bin/ruby extconf.rb checking … Read more
I’m setting up my PostgreSQL 9.1. I can’t do anything with PostgreSQL: can’t createdb, can’t createuser; all operations return the error message Fatal: role h9uest does not exist h9uest is my account name, and I sudo apt-get install PostgreSQL 9.1 under this account. Similar error persists for the root account. 17 s 17 Use the … Read more
I’m getting the error: FATAL: Peer authentication failed for user “postgres” when I try to make postgres work with Rails. Here’s my pg_hba.conf, my database.yml, and a dump of the full trace. I changed authentication to md5 in pg_hba and tried different things, but none seem to work. I also tried creating a new user … Read more
What is the easiest way to save PL/pgSQL output from a PostgreSQL database to a CSV file? I’m using PostgreSQL 8.4 with pgAdmin III and PSQL plugin where I run queries from. 17 s 17 Do you want the resulting file on the server, or on the client? Server side If you want something easy … Read more
Final update: I had forgotten to run the initdb command. By running this command ps auxwww | grep postgres I see that postgres is not running > ps auxwww | grep postgres remcat 1789 0.0 0.0 2434892 480 s000 R+ 11:28PM 0:00.00 grep postgres This raises the question: How do I start the PostgreSQL server? … Read more
I’m in a corporate environment (running Debian Linux) and didn’t install it myself. I access the databases using Navicat or phpPgAdmin (if that helps). I also don’t have shell access to the server running the database. 20 20
In MySQL, I used use database_name; What’s the psql equivalent? 1 15
How can I drop all tables in PostgreSQL, working from the command line? I don’t want to drop the database itself, just all tables and all the data in them. 30 30 If all of your tables are in a single schema, this approach could work (below code assumes that the name of your schema … Read more
How do I change the password for PostgreSQL user? 2 22 To log in without a password: sudo -u user_name psql db_name To reset the password if you have forgotten: ALTER USER user_name WITH PASSWORD ‘new_password’;
As the title suggests, I’d like to select the first row of each set of rows grouped with a GROUP BY. Specifically, if I’ve got a purchases table that looks like this: SELECT * FROM purchases; My Output: id customer total 1 Joe 5 2 Sally 3 3 Joe 2 4 Sally 1 I’d like … Read more
