On 8/12/23 13:09, Rhys A.D. Stewart wrote:
> Greetings all,
>
> I am writing a trigger and would like to know how to dynamically
> access a column from the "OLD" variable. pk_col is the column name
> from the table.
>
> I've come up with either doing this:
> EXECUTE format('SELECT $1.%1$I', pk_col) INTO pk_val USING OLD;
Got focused on pk_val = OLD[pk_col] and missed the low hanging fruit:
pk_val = OLD.pk_col
>
> which looks a bit excessive, or this
>
> pk_val = to_jsonb(OLD.*)->pk_col
>
> which looks cleaner, but then I am having to incur a little overhead
> by using the to_jsonb function. Ideally, something like this would be
> great:
>
> pk_val = OLD[pk_col]
>
> but evidently we can't subscript ROW types.
>
> Am I missing out on a simpler or more elegant solution?
>
> Rhys
> Peace & Love | Live Long & Prosper
>
>
--
Adrian Klaver
adrian.klaver@aklaver.com