What is the recommended way to map from XID8 datatype?

[podjay]

I have created a table in which I store an XID8 datatype. Is there a sensible pgtype that I can use to map from this column?

I see that there is a pgtype.XID which will map up to MaxUint32 which I'm sure will be fine (for some time) but I expected, perhaps, a pgtype.XID8.

For the people using/storing XID8, how are you reading and interpreting this using pgx?

Thanks!

[jackc]

At the moment there is no support for xid8. You would have to scan it to a string and parse it yourself or cast it to a bigint in PostgreSQL.

However, I just made a PR to add support for unsigned 64 bit integers like xid8. #2142. It's basically just find and replace of the existing uint32 code. See if that works for you.

[podjay]

Hey @jackc; thank you for the insight and quick implementation. I gave the pgx/v5 version a whirl locally in my project (we currently have some pgx/v4 types) and I didn't have great success when querying the raw XID8 value - the uint64 scanner seemed always return cannot scan []uint8.

I also noticed that I was unable to cast to bigint - my version of postgres (15.8) didn't seem to like it; I got an error like: pq: cannot cast type xid8 to bigint so presumably that is not an option.

However, I'll do some more investigation on casting xid8::text and back because that looks like it will get me quite far.

Thanks again!