Re: [Tarantool-patches] [PATCH v1 1/1] sql: remove implicit cast for COMPARISON

[Nikita Pettik <korablev@tarantool.org>]

On 30 Mar 00:29, Vladislav Shpilevoy wrote:
> Hi! Thanks for the patch!
> 
> See 15 comments below.
> 
> I don't think I understood all the changed (because I am very out of
> context), so I will revisited many of them when you send v2.
> 
> On 20/03/2020 13:34, imeevma@tarantool.org wrote:
> > This patch removes implicit cast for comparison. Also, it make
> > search using an index work the same way as in case of fullscan in
> > most cases.
> > 
> > Closes #4230
> > Closes #4783
> > ---
> > https://github.com/tarantool/tarantool/issues/4230
> > https://github.com/tarantool/tarantool/issues/4783
> > https://github.com/tarantool/tarantool/tree/imeevma/gh-4230-remove-implicit-cast-for-index-search-second
> > 
> > @ChangeLog Remove implicit cast for comparison gh-4230
> 
> 1. Worth adding more details. What implicit cast? All of them?
> 
> Do we need a docbot request for this?

We definitely do need a docbot request. What is more, I'd explicitly
agree all user-visible changes introduced in this patch with Peter
Gulutzan. If Peter is already OK with it, Mergen, could you please
copy link to the corresponding mail (cause I've a bit lost in all
'cast' threads).
 
> > diff --git a/src/box/sql/sqlInt.h b/src/box/sql/sqlInt.h
> > index 1579cc9..cd626bd 100644
> > --- a/src/box/sql/sqlInt.h
> > +++ b/src/box/sql/sqlInt.h
> > @@ -1304,6 +1304,9 @@ enum trim_side_mask {
> >  				 (X) == FIELD_TYPE_UNSIGNED || \
> >  				 (X) == FIELD_TYPE_DOUBLE)
> >  
> > +#define sql_mp_type_is_numeric(X)  ((X) == MP_INT || (X) == MP_UINT || \
> > +				    (X) == MP_FLOAT || (X) == MP_DOUBLE)
> 
> 
> 7. Is there a ticket to stop conveting MEM_* to MP_*?

Hm, I thought I created once such ticket, but in fact failed to
find it. If you are OK with suggestion below concerning splitting
mem type into two members, I'll open an issue.

> MP_* now contains all MEM_* and even more, right?

Not exactly. There are also VDBE specific MEMs like
MEM_Frame, MEM_Cleared, MEM_TypeMask etc, and auxiliary
MEMs - MEM_Dyn, MEM_Static, MEM_Ephem (i.e. allocation policy),
MEM_Subtype, MEM_Agg and so forth. I guess still we can split
struct mem->type into mp_type and aux_flags.