Documentation Home
MySQL 5.6 Reference Manual
Related Documentation Download this Manual
PDF (US Ltr) - 31.2Mb
PDF (A4) - 31.2Mb
PDF (RPM) - 29.5Mb
HTML Download (TGZ) - 7.3Mb
HTML Download (Zip) - 7.3Mb
HTML Download (RPM) - 6.2Mb
Man Pages (TGZ) - 179.4Kb
Man Pages (Zip) - 289.5Kb
Info (Gzip) - 3.0Mb
Info (Zip) - 3.0Mb
Excerpts from this Manual

MySQL 5.6 Reference Manual  /  Character Sets, Collations, Unicode  /  Restrictions on Character Sets

10.11 Restrictions on Character Sets

  • Identifiers are stored in mysql database tables (user, 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.

  • The ucs2, utf16, utf16le, and utf32 character sets have the following restrictions:

    • None of them can be used as the client character set. See Impermissible Client Character Sets.

    • It is currently not possible to use LOAD DATA to load data files that use these character sets.

    • FULLTEXT indexes cannot be created on a column that uses any of these character sets. However, you can perform IN BOOLEAN MODE searches on the column without an index.

    • The use of ENCRYPT() with these character sets is not recommended because the underlying system call expects a string terminated by a zero byte.

  • The REGEXP and RLIKE operators 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.