Server handles truncation for assignment of too-long values
into CHAR/VARCHAR/TEXT columns in a different ways when the
truncated characters are spaces:
1. CHAR(N) columns silently ignore end-space truncation;
2. TEXT columns post a truncation warning/error in the
   non-strict/strict mode.
3. VARCHAR columns always post a truncation note in
   any mode.

Space truncation processing has been synchronised over
CHAR/VARCHAR/TEXT columns: current behavior of VARCHAR
columns has been propagated as standard.

Binary-encoded string/BLOB columns are not affected.