On Tue, Jun 16, 2026 at 10:34 AM Robert Haas <[email protected]> wrote:
> On Tue, Jun 16, 2026 at 8:04 AM Etsuro Fujita <[email protected]> > wrote: > > I thought it would be a good idea to use > > pg_restore_attribute_stats/pg_restore_relation_stats, because future > > changes in attribute/relation stats would be absorbed by these > > functions, which would lower the maintenance cost of this feature. > > I agree that we want to reuse code, but this isn't the right way to do > it. For example, when we want to look up the OID of a relation from > SQL, we can say 'whatever'::regclass::oid. But when we want to do the > same thing from C, we don't construct a SELECT statement and execute > it via SPI. Instead, we have functions like RangeVarGetRelidExtended() > which provide access to the same underlying functionality more > directly. > > Another example is converting strings to integers. The user calls > int4in(), which then hands off the call to pg_strtoint32_safe(), which > can also be called via pg_strtoint32(). Hence, C code should prefer to > use pg_strtoint32(), while SQL will go through int4in(). Both > ultimately reach the underlying pg_strtoint32_safe() function, but the > interfaces are different, so that we can have it be suitable both for > SQL access and for C access. > > This needs to work more like that. The underlying code that ingests > and updates the stats should be shared, but the stuff that is specific > to a FunctionCallInfo interface needs to be separated out so that we > don't need to go through that when calling from C. > > Back when pg_restore_attribute_stats and pg_restore_relation_stats were being converted from positional to variadic functions, there was a patchset or two (possibly un-posted, because I couldn't find it just now) where the variadic functions re-marshalled the arguments into a call to a fixed-parameter function. If that model were revived, we could have a more conventional DirectFunctonCall() interface. Is it possible that we never built a direct function call interface to a variadic because we never needed one? Perhaps that time is now.
