To install SQL-Ledger:

Install PostgreSQL per your operating system requirements.

Most installations create a special user postgres that is used to start and stop the PostgresSQL database.  

root@localhost#  su  postgres

postgres@localhost:/etc$   initdb -D /var/lib/postgresql/data

postgres@localhost:/etc$ exit 

Start the PostgreSQL database based on your operating system.
For Slackware:

root@localhost/:# chmod +x /etc/rc.d/rc.postgresql

root@localhost:/#  /etc/apache# /etc/rc.d/rc.postgres   start

root@localhost:/#  su  postgres

postgres@localhost:/etc$ createuser -d sql-ledger                           

Shall the new user be allowed to create more new users? (y/n) y
CREATE USER

postgres@localhost:/etc$ createlang plpgsql template1

postgres@localhost:/etc$ exit

root@localhost#

Edit sql-ledger.conf (if you want).  The sql-ledger.conf that comes with OpenEMR should work but the paths may need to altered. 

Create a file sql-ledger-httpd.conf in the same location
 where your httpd.conf is and copy the next section into the file
In my example I will
root@localhost#  touch   /etc/apache/sql-ledger-httpd.conf
Then add:

  Alias /sql-ledger /usr/local/sql-ledger/
  <Directory /usr/local/sql-ledger>
    AllowOverride All
    AddHandler cgi-script .pl
    Options ExecCGI Includes FollowSymlinks
    Order Allow,Deny
    Allow from All
  </Directory>

  <Directory /usr/local/sql-ledger/users>
    Order Deny,Allow
    Deny from All
  </Directory>

Edit httpd.conf and add

 # SQL-Ledger
 Include /etc/apache/sql-ledger-httpd.conf

Save the httpd.conf and restart your apache web server.

For slackware:

root@localhost:/#  /etc/apache# /etc/rc.d/rc.httpd stop
root@localhost:/#  /etc/apache# /etc/rc.d/rc.httpd start

I moved to my sql-ledger directory:

root@localhost:/etc/apache#  cd  /usr/local/sql-ledger/

And changed the owner of directories:  users templates css spool

root@localhost:/usr/local/sql-ledger# chown -R nobody:nobody users templates css spool

SQL-Ledger requires perl 5+, DBI, DBD-Pg.  I had to use cpan to install a few perl modules: Frontier::Responder and DBI and DBD:Pg 

#  perl -MCPAN -e 'install Bundle::DBI'
#  perl -MCPAN -e 'install Class::DBI::Pg'
#  perl -MCPAN -e 'install Frontier::Responder'

# exit

Use your web browser to connect to SQL-Ledger with:

http://localhost/sql-ledger/admin.pl

The initial password is "pass123"

Select:

change admin password

After creating a new password

Select:

Create dataset

make a new dataset name (all small case). I created:

demoledger

Add User:

drbowen

enter the host, postgres user, port, postgres password and dataset

for me 

host:           localhost 
user:          sql-ledger
port:           5432
password:  1234abdDCX!
dataset:      demoledger

Click on the save button.

Open a new browser window and you should be able to log on at:

http://localhost/sql-ledger/