Check if two tables are equal
Snowflake has two hash functions: HASH and HASH_AGG. These aren’t cryptographic hashes but a way go group/compare values.
To compare two tables:
select hash_agg(*) = (select hash_agg(*) from x) from y;
Check how many times colums from a table have been used
select obj:objectName::string as object_name, col:columnName::string as column_name, count(*) as uses, min(query_start_time) as since, max(query_start_time) as until from snowflake.account_usage.access_history, table(flatten(direct_objects_accessed)).value obj, table(flatten(obj.vale:columns)).value col where starts_with(object_name, "<prefix of the object you want to inspect>") group by 1, 2 order by uses desc
Refresh external table
alter external table <external-table> refresh;