Re: ToDo: fast update of arrays with fixed length fields for PL/pgSQL

On 2013-10-07 16:00:54 +0200, Pavel Stehule wrote:
> /*
> * We need to do subscript evaluation, which might require
> @@ -4321,6 +4322,14 @@ exec_assign_value(PLpgSQL_execstate *estate,
> oldarrayval = (ArrayType *) DatumGetPointer(oldarraydatum);
>
> /*
> + * support fast update for array scalar variable is enabled only
> + * when target is a scalar variable and variable holds a local
> + * copy of some array.
> + */
> + inplace_update = (((PLpgSQL_datum *) target)->dtype == PLPGSQL_DTYPE_VAR
> + && ((PLpgSQL_var *) target)->freeval);
> +
> + /*
> * Build the modified array value.
> */

Will this recognize if the local Datum is just a reference to an
external toast Datum (i.e. varattrib_1b_e)?

I don't know much about plpgsql's implementation, so please excuse if
the question is stupid.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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