KB441548: Poor Performance when using VARCHAR column in Snowflake

Actual behavior

While fetching data from a table containing VARCHAR or VARCHAR(16777216) columns there is a significant increase in the fetch time.   This will occur if a Snowflake administrator creates a table with columns defined as "VARCHAR" and does not specify a size.  This is the equivalent to setting the VARCHAR size to the maximum allowed which is 16MB (16777216).  Strategy Intelligence Server uses an ODBC Call (SQLDescribeCol) to determine the proper resources to allocate for the query results for VARCHAR columns this will lead to performance degradation.
This is due to the fact that the user allocates resources in anticipation of a very large amount of data (even if the string is only a few hundred characters max). VARCHAR(16777216) will define boundary for more size and affect the performance while fetching.

Workaround

To fix this issue, the customer has a few options:

1. Change the VARCHAR data type in Snowflake to use a smaller size (ALTER TABLE...ALTER COLUMN).
2. Recreate the table and with the smaller VARCHAR length and reload the data.
3. Create a view where the VARCHAR(16777216) values are cast to a smaller size.