Identifiers are stored in
mysqldatabase tables (
db, and so forth) using
utf8, but identifiers can contain only characters in the Basic Multilingual Plane (BMP). Supplementary characters are not permitted in identifiers.
ucs2character sets has the following restrictions:
It cannot be used as a client character set, which means that it does not work for
SET CHARACTER SET. (See Connection Character Sets and Collations.)
It is currently not possible to use
LOAD DATA INFILEto load data files that use this character set.
FULLTEXTindexes cannot be created on a column that this character set. However, you can perform
IN BOOLEAN MODEsearches on the column without an index.
The use of
ENCRYPT()with this character set is not recommended because the underlying system call expects a string terminated by a zero byte.
RLIKEoperators work in byte-wise fashion, so they are not multibyte safe and may produce unexpected results with multibyte 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.