On Thu, Jun 23, 2022 at 2:07 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > Sounds worth investigating, anyway. It'd also get us out from under > C-struct-related problems such as the nearby AIX alignment issue.
Yeah. > The extra cost of the deforming step could also be repaid, in some > cases, by not having to use SysCacheGetAttr etc later on to fetch > variable-length fields. That is, I'm imagining that the deformer > would extract all the fields, even varlena ones, and drop pointers > or whatever into fields of the C struct. Yeah, if we were going to do something like this, I can't see why we wouldn't do it this way. It wouldn't make sense to do it for only some of the attributes. I'm not sure exactly where we would put this translation step, though. I think for the syscaches and relcache we'd want to translate when populating the cache so that when you do a cache lookup you get the data already translated. It's hard to be sure without testing, but that seems like it would make this cheap enough that we wouldn't have to be too worried, since the number of times we build new cache entries should be small compared to the number of times we access existing ones. The trickier thing might be code that uses systable_beginscan() et. al. directly. -- Robert Haas EDB: http://www.enterprisedb.com
