Remove RC from certain Owned Value Types and look for DX friendly ways to implement Zerocopy Result Row

[pedrocarlo]

Exploration PR to look for ways to increase performance with hopefully minimal use of lifetimes

[penberg]

Hey @pedrocarlo! It's not clear to me what you're planning to do here. The Rc there is to avoid expensive copies of the values, which is important in cases where OwnedValue owns the values (SQLite calls them dynamic values). However, for zero copy what we need is a way to represent values that are not owned by OwnedValue (terrible name now) and instead are just pointers to something else (called static values in SQLite IIRC).

[pedrocarlo]

Hey @penberg! So this is PR is still a bit in the exploration phase. As you mentioned in #906, we should try teaching the code "about blobs and strings that are managed by someone else". The first thought I had in mind was maybe using a Cow so that clones are minimized, and it would clearly indicate if the value is owned or not. But, Im still trying to figure out if this is the right way, that is why there is no commit yet regarding some Cow implementation. However, I do not think this addresses our issue. I'm still a bit unexperienced with Rust so I am still searching for ways to do it. If you have any ideas I am all ears!