https://docs.snowflake.net/manuals/user-guide/intro-summary-loading.html#encryption-of-staged-files

The data loading wizard being browser based, is intended for loading for small files. The data loading wizard uses the COPY & PUT command behind the scenes, there for it requires an active virtual warehouse connection.

https://docs.snowflake.net/manuals/user-guide/data-load-web-ui.html

All 3 are correct options. You can specify either in the table definition it self https://docs.snowflake.net/manuals/sql-reference/sql/create-table.html#format-type-options-formattypeoptions You can define a named file format and use that in the copy command, or you can directly specify your file format in the copy command https://docs.snowflake.net/manuals/user-guide/data-unload-prepare.html#specifying-file-format-options

When using a query to unload data from Snowflake, you are allowed the full SQL capabilities, including joining with other tables, grouping etc. https://docs.snowflake.net/manuals/user-guide/data-unload-overview.html#bulk-unloading-using-queries

Correct. Since multiple processes are reading from the queue, there is no guarantee that the files will be loaded in the exact order that they arrived. https://docs.snowflake.net/manuals/user-guide/data-load-snowpipe-intro.html#load-order-of-data-files

External table is the easiest way to query data in an external stage without loading it first into Snowflake. https://docs.snowflake.net/manuals/user-guide/tables-external-intro.html

Split large files into smaller files of 10-100 MB after compression. The number of files will generally be proportional to the number of servers in the virtual warehouse being used to load the data . https://docs.snowflake.net/manuals/user-guide/data-load-considerations-prepare.html#file-sizing-best-practices-and-limitations

All of these are treated as VARCHAR data type by Snowflake, with the following caveats. CHAR & CHARACTER default to size "1" if no size is specified

https://docs.snowflake.net/manuals/sql-reference/data-types-text.html#char-character https://docs.snowflake.net/manuals/sql-reference/data-types-text.html#string-text

All data at rest i.e. data in tables, data in internal stages etc.. Is encrypted automatically. Snowflake internal stages are also automatically encrypted. Since data in external stages is usually managed by a customer, automatic encryption is not applied on files on external stages, how ever they can be encrypted optionally

https://docs.snowflake.net/manuals/user-guide/security-encryption.html

VARIANT can store up to 16 MB of compressed data and any data type can be cast to VARIANT https://docs.snowflake.net/manuals/sql-reference/data-types-semistructured.html#variant