<title>Creating database</title>

        <title>Creating the database</title>

            Hydra stores its results in a PostgreSQL database. To setup a database with <emphasis>hydra</emphasis> as database name and username, issue the following commands:

            Hydra stores its results in a database, which can be a
            PostgreSQL or SQLite database.  The latter is easier to
	    setup, but the former scales better.
	</para>
	<para>To setup a PostgreSQL
            database with <emphasis>hydra</emphasis> as database name
            and user name, issue the following commands:

            Note that <emphasis>$prefix</emphasis> is the location of Hydra in the nix store.

            Note that <emphasis>$prefix</emphasis> is the location of
	    Hydra in the nix store.
	</para>
	<para>
	    For SQLite, the following command is all it takes to
	    create the database:
	    <screen>
	      cat $prefix/share/hydra/sql/hydra-sqlite.sql | sqlite3 /path/to/hydra.sqlite
	    </screen>

echo "INSERT INTO UserRoles(userName, role) values('root', 'admin');" | psql hydra</screen>

echo "INSERT INTO UserRoles(userName, role) values('root', 'admin');" | psql hydra
	    </screen>
	    For SQLite the same commands can be used, with
	    <command>psql hydra</command> replaced by
	    <command>sqlite3 /path/to/hydra.sqlite</command>.
	</para>

            Hydra uses an environment variable to know which database should be used, and a variable which point to a location that holds some state. To set these 
            variables, add the following to the <emphasis>.profile</emphasis> of the user running the Hydra services.

	<para>
            Hydra uses an environment variable to know which database
            should be used, and a variable which point to a location
            that holds some state. To set these variables for a
            PostgreSQL database, add the following to the
            <filename>.profile</filename> of the user running the
            Hydra services.

            Make sure that the <emphasis>HYDRA_DATA</emphasis> directory exists and is writable for the user which will run the Hydra services.

            Make sure that the <emphasis>HYDRA_DATA</emphasis>
            directory exists and is writable for the user which will
            run the Hydra services.  For a SQLite database, the
            <varname>HYDRA_DBI</varname> should be set to something
            like <literal>dbi:SQLite:/path/to/hydra.sqlite</literal>