MySQL Reference Manual :: D.8.3 Changes in release 3.19.3

Fixed SELECT with grouping on BLOB columns not to return incorrect BLOB info. Grouping, sorting and distinct on BLOB columns does not yet work as expected (probably it groups/sorts by the first 7 characters in the BLOB). Grouping on formulas with a fixed string size (use MID() on a BLOB) should work.

When doing a full join (no direct keys) on multiple tables with BLOB fields, the BLOB was garbage on output.

Fixed DISTINCT with calculated columns.