Postgres 13 or lower don't have predefined roles, so we call unnest on an empty python array which is emitted as '{}'. This is ambiguous for postgres so we need to explicitly cast the value as an array of text, which works for both an empty array and a non empty array (which is emitted as ARRAY[...]).
Postgres 13 or lower don't have predefined roles, so we call unnest on an empty python array which is emitted as '{}'. This is ambiguous for postgres so we need to explicitly cast the value as an array of text, which works for both an empty array and a non empty array (which is emitted as ARRAY[...]).