Re: A way of storing variables - will this work?

On Wed, 27 Jun 2001, Edmund von der Burg wrote:

> Hello,
>
> For a project I am working on I needed some way of storing a variable for
> the duration of a session and cooked this up, based on some previous posts
> to this list:
>
>
> create sequence variable_id_seq;
>
> create table variables (
> id integer
> primary key
> default nextval('variable_id_seq'),
> value integer
> );
>
> create function set_var(integer)
> returns integer
> as 'insert into variables (value) values ($1);
> select $1 as variable;'
> language 'sql';
>
> create function get_var()
> returns integer
> as 'select value
> from variables
> where id = currval(''variable_id_seq'');'
> language 'sql';
>
>
> Basically you set the variable using set_var(1234) and then get it back
> using get_var().
>
> I have tested this in as mawy ways as I can think of, but is there
> any reason why it should not work? It will be used to store the access
> level of the user and so to implement a security policy inside the
> database.

If everything runs inside a transaction, there is no issue with regard to concurrency and getting th ecorrect value with currval() through get_var().

cheers,
thalis

>
> Many thanks,
>
> Edmund.
>
> --
> ***********************************************************
> *** Edmund von der Burg *** edmund(at)ecclestoad(dot)co(dot)uk ***
> *** Eccles & Toad *** http://www.ecclestoad.co.uk ***
> ***********************************************************
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