Identifiers are stored in
db, and so
utf8, but identifiers can
contain only characters in the Basic Multilingual Plane (BMP).
Supplementary characters are not permitted in identifiers.
character sets have the following restrictions:
They cannot be used as a client character set, which means
that they do not work for
SET NAMES or
SET CHARACTER SET. (See
Section 10.1.4, “Connection Character Sets and Collations”.)
It is currently not possible to use
INFILE to load data files that use these
FULLTEXT indexes cannot be created on a
column that uses any of these character sets. However, you
IN BOOLEAN MODE searches on
the column without an index.
The use of
these character sets is not recommended because the
underlying system call expects a string terminated by a
operators work in byte-wise fashion, so they are not
multi-byte safe and may produce unexpected results with
multi-byte character sets. In addition, these operators
compare characters by their byte values and accented
characters may not compare as equal even if a given collation
treats them as equal.