> -----Original Message-----
> From: Dmitry Yemanov [mailto:firebi...@yandex.ru]
> Sent: Martes, 09 de Junio de 2015 6:19
>
> 09.06.2015 13:11, Dimitry Sibiryakov wrote:
> >
> > ISQL would better always report "Rows affected" as a sum of
> all three components of
> > info response: inserts+updates+deletes.
>
> Sounds as a good short-term solution. Does anyone see
> problems with this
> approach?
I would like to be able to know that I'm dealing with MERGE or any other
statement that can lead to an update and/or insert. Adding
inserts+updates+deletes is not a problem (indeed, it's simpler code), but
it's a departure of the traditional logic. The current code provides the
result of the direct action of the statement. See this contrived example:
create table master(a int primary key);
create table detail(b int primary key, master_a int not null references
master(a));
insert into master values(0);
insert into master values(1);
insert into master values(2);
commit;
insert into detail values(10, 0);
insert into detail values(11, 1);
insert into detail values(12, 2);
commit;
set term ^;
create trigger tr_mod for master before update as begin
if (new.a != old.a) then
delete from detail where master_a = old.a;
end ^
set term ;^
update master set a = -1 where a = 0;
^Z
With the old logic, the result is one. With the new logic, the result is two
becaise we get the direct and indirect effects. Confusing to the end user?
DSQL's get_request_info() retrieves not only the changes but the selected
records, too so we still need to filter out those. BTW, both isql.epp and
StatementMetadata.cpp do basically the same parsing:
if (result[0] == isc_info_sql_records)
{
const UCHAR* p = result + 3;
while (*p != isc_info_end)
{
UCHAR counter = *p++;
const SSHORT len = gds__vax_integer(p, 2);
p += 2;
if (counter != isc_info_req_select_count)
count += gds__vax_integer(p, len);
p += len;
}
}
Has anybody thought what will we reported in the extreme event of more than
2^32 updated or deleted records? The counters are going to overflow because
they are ULONG in the engine.
C.
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