Support persist_docs for view columns in Snowflake

[spencer-taylor-workrise]

Describe the feature

Currently persist_docs is available for relations in Snowflake, but view column documentation is not supported. This would implement that support.

Additional context

This has been proposed in issues #2334 and #1574. Both of these issues have been closed, but implementation at the view column level wasn't completed.

Who will this benefit?

This will be useful for Snowflake users who prefer to store column-level metadata for their views in the database.

Are you interested in contributing this feature?

I'm more than happy to contribute this feature 😄

[jtcohen6]

@spencer-taylor-workrise Are you thinking about persisting column-level descriptions for Snowflake views? If so, I think we've already got an issue for this, over in #17. You can check out my response in #17 (comment) for a sense of what makes this tricky to implement.

It sounds like you're interested in contributing the feature, which is great! Let's continue the discussion started in #17, and talk about what the least-bad approach might be, since it doesn't seem like either of these is coming any time soon:

alter view <view_name> alter column <column_name> comment
comment on column <view_name>.<column_name>

[spencer-taylor-workrise]

That sounds good @jtcohen6 ! Thanks for confirming, must have missed that issue when I was looking around in dbt core 😄