Explanation
Stream Columns
A stream stores an offset for the source object and not any actual table columns or data. When que-ried, a stream accesses and returns the historic data in the same shape as the source object (i.e. the same column names and ordering) with the following additional columns:
METADATA$ACTION
Indicates the DML operation (INSERT, DELETE) recorded.
METADATA$ISUPDATE
Indicates whether the operation was part of an UPDATE statement. Updates to rows in the source object are represented as a pair of DELETE and INSERT records in the stream with a metadata column METADATA$ISUPDATE values set to TRUE.
METADATA$ROW_ID
Specifies the unique and immutable ID for the row, which can be used to track changes to specific rows over time.
Note that streams record the differences between two offsets. If a row is added and then updated in the current offset, the delta change is a new row. The METADATA$ISUPDATE row records a FALSE value.

Explanation
Snowflake's zero-copy cloning feature provides a convenient way to quickly take a "snapshot" of any table, schema, or database and create a derived copy of that object which initially shares the underlying storage. This can be extremely useful for creating instant backups that do not incur any additional costs (until changes are made to the cloned object).
For example, when a clone is created of a table, the clone utilizes no data storage because it shares all the existing micro-partitions of the original table at the time it was cloned; however, rows can then be added, deleted, or updated in the clone independently from the original table. Each change to the clone results in new micro-partitions that are owned exclusively by the clone and are protect-ed through CDP.

Explanation
LAST_QUERY_ID() Function
Returns the ID of a specified query in the current session. If no query is specified, the most recently executed query is returned.
RESULT_SCAN() Function
Returns the result set of a previous command (within 24 hours of when you executed the query) as if the result was a table.
The following example validates a set of files (SFfile.csv.gz) that contain errors. To facilitate analy-sis of the errors, a COPY INTO <location> statement then unloads the problematic records into a text file so they could be analyzed and fixed in the original data files. The statement queries the RESULT_SCAN table.
1.#copy into Snowtable
2.from @SFstage/SFfile.csv.gz
3.validation_mode=return_all_errors;
4.#set qid=last_query_id();
5.#copy into @SFstage/errors/load_errors.txt from (select rejected_record from ta-ble(result_scan($qid))); Note: Other options are not valid functions.