Re: pgbench - add \aset to store results of a combined query

Bonjour Michaël,

> [...] Still sounds strange to me to invent a new variable to this 
> structure if it is possible to track the exact same thing with an 
> existing part of a Command, or it would make sense to split Command into 
> two different structures with an extra structure used after the parsing 
> for clarity?

Hmmm.

Your point is to store the gset/aset status into the meta field, even if 
the command type is SQL. This is not done for gset, which relies on the 
non-null prefix, and breaks the assumption that meta is set to something 
only when the command is a meta command. Why not. I updated the comment, 
so now meta is none/gset/aset when command type is sql, and I removed the 
aset field.

> Well, it still looks cleaner to me to just assign the meta field
> properly within ParseScript(), and you get the same result.  And it is
> also possible to use "meta" to do more sanity checks around META_GSET
> for some code paths.  So I'd actually find the addition of a new
> argument using a meta command within readCommandResponse() cleaner.

I tried to do that.

> - * varprefix   SQL commands terminated with \gset have this set
> + * varprefix   SQL commands terminated with \gset or \aset have this set

> Nit from v4: varprefix can be used for \gset and \aset, and the
> comment was not updated.

It is now updated.

> +                   /* coldly skip empty result under \aset */
> +                   if (ntuples <= 0)
> +                       break;
> Shouldn't this check after \aset?  And it seems to me that this code
> path is not taken, so a test would be nice.

Added (I think, if I understood what you suggested.).

> -   } while (res);
> +   } while (res != NULL);
> Useless diff.

Yep.

Attached an updated v5.

-- 
Fabien.