For the latest dbt-postgres version (1.7.4) as well as a historical version (1.5.2), I cannot add an array field to a snapshot after adding the array field to the underlying snapshotted model.
In particular, the alter table command in the adaptor errors due to inaccurate syntax. The adaptor does
add column blah array rather than
add column blah integer array when
dbt snapshot is run. In other words, we need to specify a data type when adding an array to a schema in postgres.
See postgres documentation.
I have a snapshot model where we added an array to the underlying snapshotted table.
Upgrading dbt-postgres to the latest version.