diff options
Diffstat (limited to 'sql/item_strfunc.h')
| -rw-r--r-- | sql/item_strfunc.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h index a279dd8598f..c0505773ba8 100644 --- a/sql/item_strfunc.h +++ b/sql/item_strfunc.h @@ -1441,11 +1441,19 @@ public: /* Conversion from and to "binary" is safe. Conversion to Unicode is safe. + Conversion from an expression with the ASCII repertoire + to any character set that can store characters U+0000..U+007F + is safe: + - All supported multibyte character sets can store U+0000..U+007F + - All supported 7bit character sets can store U+0000..U+007F + except those marked with MY_CS_NONASCII (e.g. swe7). Other kind of conversions are potentially lossy. */ safe= (args[0]->collation.collation == &my_charset_bin || cs == &my_charset_bin || - (cs->state & MY_CS_UNICODE)); + (cs->state & MY_CS_UNICODE) || + (args[0]->collation.repertoire == MY_REPERTOIRE_ASCII && + (cs->mbmaxlen > 1 || !(cs->state & MY_CS_NONASCII)))); } } bool is_json_type() { return args[0]->is_json_type(); } |