Feature: Decimal data type support for currency fields

[everpcpc]

Summary

for storing money in databend

[sundy-li]

It can be addressed in #6547

[youngsofun]

I already did some investigation after taking this issue https://github.com/datafuselabs/databend/issues/2931 I planned to add it after plan v2 is applied and new type systems are used. @sundy-li do you mean we can add it now in common-expression first?

[sundy-li]

do you mean we can add it now in common-expression first?

Yes, we can add it now, it may take some time to make it to production.

[BohuTANG]

Will databend support int128 firstly?

[youngsofun]

Will databend support int128 firstly? yes

[youngsofun]

dup with https://github.com/datafuselabs/databend/issues/2931， close it