Due to a possible significant inconsistency in real and estimated number of rows (and table sizes) on the MySQL Storage backend which could lead to data loss when editing the data sample, we turned off the data sample editing for all IN and OUT MySQL buckets. SYS buckets are fully editable and will always show and edit all available rows.
Redshift works as expected - editing is allowed for all tables if they contain less than 800 cells (excluding headers).
