MySQL supports 70+ collations for 30+ character sets. This section indicates which character sets MySQL supports. There is one subsection for each group of related character sets. For each character set, the allowable collations are listed.
You can always list the available character sets and their default
collations with the SHOW CHARACTER SET
statement:
mysql> SHOW CHARACTER SET;
+----------+-----------------------------+---------------------+
| Charset | Description | Default collation |
+----------+-----------------------------+---------------------+
| big5 | Big5 Traditional Chinese | big5_chinese_ci |
| dec8 | DEC West European | dec8_swedish_ci |
| cp850 | DOS West European | cp850_general_ci |
| hp8 | HP West European | hp8_english_ci |
| koi8r | KOI8-R Relcom Russian | koi8r_general_ci |
| latin1 | cp1252 West European | latin1_swedish_ci |
| latin2 | ISO 8859-2 Central European | latin2_general_ci |
| swe7 | 7bit Swedish | swe7_swedish_ci |
| ascii | US ASCII | ascii_general_ci |
| ujis | EUC-JP Japanese | ujis_japanese_ci |
| sjis | Shift-JIS Japanese | sjis_japanese_ci |
| hebrew | ISO 8859-8 Hebrew | hebrew_general_ci |
| tis620 | TIS620 Thai | tis620_thai_ci |
| euckr | EUC-KR Korean | euckr_korean_ci |
| koi8u | KOI8-U Ukrainian | koi8u_general_ci |
| gb2312 | GB2312 Simplified Chinese | gb2312_chinese_ci |
| greek | ISO 8859-7 Greek | greek_general_ci |
| cp1250 | Windows Central European | cp1250_general_ci |
| gbk | GBK Simplified Chinese | gbk_chinese_ci |
| latin5 | ISO 8859-9 Turkish | latin5_turkish_ci |
| armscii8 | ARMSCII-8 Armenian | armscii8_general_ci |
| utf8 | UTF-8 Unicode | utf8_general_ci |
| ucs2 | UCS-2 Unicode | ucs2_general_ci |
| cp866 | DOS Russian | cp866_general_ci |
| keybcs2 | DOS Kamenicky Czech-Slovak | keybcs2_general_ci |
| macce | Mac Central European | macce_general_ci |
| macroman | Mac West European | macroman_general_ci |
| cp852 | DOS Central European | cp852_general_ci |
| latin7 | ISO 8859-13 Baltic | latin7_general_ci |
| cp1251 | Windows Cyrillic | cp1251_general_ci |
| cp1256 | Windows Arabic | cp1256_general_ci |
| cp1257 | Windows Baltic | cp1257_general_ci |
| binary | Binary pseudo charset | binary |
| geostd8 | GEOSTD8 Georgian | geostd8_general_ci |
| cp932 | SJIS for Windows Japanese | cp932_japanese_ci |
| eucjpms | UJIS for Windows Japanese | eucjpms_japanese_ci |
+----------+-----------------------------+---------------------+
MySQL has two Unicode character sets. You can store text in about 650 languages using these character sets.
ucs2
(UCS-2 Unicode) collations:
ucs2_bin
ucs2_czech_ci
ucs2_danish_ci
ucs2_esperanto_ci
ucs2_estonian_ci
ucs2_general_ci
(default)
ucs2_hungarian_ci
ucs2_icelandic_ci
ucs2_latvian_ci
ucs2_lithuanian_ci
ucs2_persian_ci
ucs2_polish_ci
ucs2_roman_ci
ucs2_romanian_ci
ucs2_slovak_ci
ucs2_slovenian_ci
ucs2_spanish2_ci
ucs2_spanish_ci
ucs2_swedish_ci
ucs2_turkish_ci
ucs2_unicode_ci
utf8
(UTF-8 Unicode) collations:
utf8_bin
utf8_czech_ci
utf8_danish_ci
utf8_esperanto_ci
utf8_estonian_ci
utf8_general_ci
(default)
utf8_hungarian_ci
utf8_icelandic_ci
utf8_latvian_ci
utf8_lithuanian_ci
utf8_persian_ci
utf8_polish_ci
utf8_roman_ci
utf8_romanian_ci
utf8_slovak_ci
utf8_slovenian_ci
utf8_spanish2_ci
utf8_spanish_ci
utf8_swedish_ci
utf8_turkish_ci
utf8_unicode_ci
Note that in the ucs2_roman_ci
and
utf8_roman_ci
collations,
I
and J
compare as equals,
and U
and V
compare as
equals.
The ucs2_esperanto_ci
and
utf8_esperanto_ci
collations were added in
MySQL 5.0.13. The ucs2_hungarian_ci
and
utf8_hungarian_ci
collations were added in
MySQL 5.0.19.
MySQL implements the utf8_unicode_ci
collation according to the Unicode Collation Algorithm (UCA)
described at
http://www.unicode.org/reports/tr10/. The
collation uses the version-4.0.0 UCA weight keys:
http://www.unicode.org/Public/UCA/4.0.0/allkeys-4.0.0.txt.
The following discussion uses
utf8_unicode_ci
, but it is also true for
ucs2_unicode_ci
.
Currently, the utf8_unicode_ci
collation has
only partial support for the Unicode Collation Algorithm. Some
characters are not supported yet. Also, combining marks are not
fully supported. This affects primarily Vietnamese and some
minority languages in Russia such as Udmurt, Tatar, Bashkir, and
Mari.
The most significant feature in
utf8_unicode_ci
is that it supports
expansions; that is, when one character compares as equal to
combinations of other characters. For example, in German and
some other languages ‘ß
’ is
equal to ‘ss
’.
utf8_general_ci
is a legacy collation that
does not support expansions. It can make only one-to-one
comparisons between characters. This means that comparisons for
the utf8_general_ci
collation are faster, but
slightly less correct, than comparisons for
utf8_unicode_ci
.
For example, the following equalities hold in both
utf8_general_ci
and
utf8_unicode_ci
:
Ä = A Ö = O Ü = U
A difference between the collations is that this is true for
utf8_general_ci
:
ß = s
Whereas this is true for utf8_unicode_ci
:
ß = ss
MySQL implements language-specific collations for the
utf8
character set only if the ordering with
utf8_unicode_ci
does not work well for a
language. For example, utf8_unicode_ci
works
fine for German and French, so there is no need to create
special utf8
collations for these two
languages.
utf8_general_ci
also is satisfactory for both
German and French, except that
‘ß
’ is equal to
‘s
’, and not to
‘ss
’. If this is acceptable for
your application, then you should use
utf8_general_ci
because it is faster.
Otherwise, use utf8_unicode_ci
because it is
more accurate.
utf8_swedish_ci
, like other
utf8
language-specific collations, is derived
from utf8_unicode_ci
with additional language
rules. For example, in Swedish, the following relationship
holds, which is not something expected by a German or French
speaker:
Ü = Y < Ö
The utf8_spanish_ci
and
utf8_spanish2_ci
collations correspond to
modern Spanish and traditional Spanish, respectively. In both
collations, ‘ñ
’ (n-tilde) is a
separate letter between ‘n
’ and
‘o
’. In addition, for traditional
Spanish, ‘ch
’ is a separate
letter between ‘c
’ and
‘d
’, and
‘ll
’ is a separate letter between
‘l
’ and
‘m
’
Western European character sets cover most West European languages, such as French, Spanish, Catalan, Basque, Portuguese, Italian, Albanian, Dutch, German, Danish, Swedish, Norwegian, Finnish, Faroese, Icelandic, Irish, Scottish, and English.
ascii
(US ASCII) collations:
ascii_bin
ascii_general_ci
(default)
cp850
(DOS West European) collations:
cp850_bin
cp850_general_ci
(default)
dec8
(DEC Western European) collations:
dec8_bin
dec8_swedish_ci
(default)
hp8
(HP Western European) collations:
hp8_bin
hp8_english_ci
(default)
latin1
(cp1252 West European) collations:
latin1_bin
latin1_danish_ci
latin1_general_ci
latin1_general_cs
latin1_german1_ci
latin1_german2_ci
latin1_spanish_ci
latin1_swedish_ci
(default)
latin1
is the default character set.
MySQL's latin1
is the same as the Windows
cp1252
character set. This means it is
the same as the official ISO 8859-1
or
IANA (Internet Assigned Numbers Authority)
latin1
, but IANA
latin1
treats the code points between
0x80
and 0x9f
as
“undefined,” whereas cp1252
,
and therefore MySQL's latin1
, assign
characters for those positions. For example,
0x80
is the Euro sign. For the
“undefined” entries in
cp1252
, MySQL translates
0x81
to Unicode
0x0081
, 0x8d
to
0x008d
, 0x8f
to
0x008f
, 0x90
to
0x0090
, and 0x9d
to
0x009d
.
The latin1_swedish_ci
collation is the
default that probably is used by the majority of MySQL
customers. Although it is frequently said that it is based
on the Swedish/Finnish collation rules, there are Swedes and
Finns who disagree with this statement.
The latin1_german1_ci
and
latin1_german2_ci
collations are based on
the DIN-1 and DIN-2 standards, where DIN stands for
Deutsches Institut für
Normung (the German equivalent of ANSI).
DIN-1 is called the “dictionary collation” and
DIN-2 is called the “phone book collation.”
latin1_german1_ci
(dictionary) rules:
Ä = A Ö = O Ü = U ß = s
latin1_german2_ci
(phone-book) rules:
Ä = AE Ö = OE Ü = UE ß = ss
In the latin1_spanish_ci
collation,
‘ñ
’ (n-tilde) is a separate
letter between ‘n
’ and
‘o
’.
macroman
(Mac West European) collations:
macroman_bin
macroman_general_ci
(default)
swe7
(7bit Swedish) collations:
swe7_bin
swe7_swedish_ci
(default)
MySQL provides some support for character sets used in the Czech Republic, Slovakia, Hungary, Romania, Slovenia, Croatia, and Poland.
cp1250
(Windows Central European)
collations:
cp1250_bin
cp1250_croatian_ci
cp1250_czech_cs
cp1250_general_ci
(default)
cp852
(DOS Central European) collations:
cp852_bin
cp852_general_ci
(default)
keybcs2
(DOS Kamenicky Czech-Slovak)
collations:
keybcs2_bin
keybcs2_general_ci
(default)
latin2
(ISO 8859-2 Central European)
collations:
latin2_bin
latin2_croatian_ci
latin2_czech_cs
latin2_general_ci
(default)
latin2_hungarian_ci
macce
(Mac Central European) collations:
macce_bin
macce_general_ci
(default)
South European and Middle Eastern character sets supported by MySQL include Armenian, Arabic, Georgian, Greek, Hebrew, and Turkish.
armscii8
(ARMSCII-8 Armenian) collations:
armscii8_bin
armscii8_general_ci
(default)
cp1256
(Windows Arabic) collations:
cp1256_bin
cp1256_general_ci
(default)
geostd8
(GEOSTD8 Georgian) collations:
geostd8_bin
geostd8_general_ci
(default)
greek
(ISO 8859-7 Greek) collations:
greek_bin
greek_general_ci
(default)
hebrew
(ISO 8859-8 Hebrew) collations:
hebrew_bin
hebrew_general_ci
(default)
latin5
(ISO 8859-9 Turkish) collations:
latin5_bin
latin5_turkish_ci
(default)
The Baltic character sets cover Estonian, Latvian, and Lithuanian languages.
cp1257
(Windows Baltic) collations:
cp1257_bin
cp1257_general_ci
(default)
cp1257_lithuanian_ci
latin7
(ISO 8859-13 Baltic) collations:
latin7_bin
latin7_estonian_cs
latin7_general_ci
(default)
latin7_general_cs
The Cyrillic character sets and collations are for use with Belarusian, Bulgarian, Russian, and Ukrainian languages.
cp1251
(Windows Cyrillic) collations:
cp1251_bin
cp1251_bulgarian_ci
cp1251_general_ci
(default)
cp1251_general_cs
cp1251_ukrainian_ci
cp866
(DOS Russian) collations:
cp866_bin
cp866_general_ci
(default)
koi8r
(KOI8-R Relcom Russian) collations:
koi8r_bin
koi8r_general_ci
(default)
koi8u
(KOI8-U Ukrainian) collations:
koi8u_bin
koi8u_general_ci
(default)
The Asian character sets that we support include Chinese,
Japanese, Korean, and Thai. These can be complicated. For
example, the Chinese sets must allow for thousands of different
characters. See Section 10.9.7.1, “The cp932
Character Set”, for additional
information about the cp932
and
sjis
character sets.
big5
(Big5 Traditional Chinese)
collations:
big5_bin
big5_chinese_ci
(default)
cp932
(SJIS for Windows Japanese)
collations:
cp932_bin
cp932_japanese_ci
(default)
eucjpms
(UJIS for Windows Japanese)
collations:
eucjpms_bin
eucjpms_japanese_ci
(default)
euckr
(EUC-KR Korean) collations:
euckr_bin
euckr_korean_ci
(default)
gb2312
(GB2312 Simplified Chinese)
collations:
gb2312_bin
gb2312_chinese_ci
(default)
gbk
(GBK Simplified Chinese) collations:
gbk_bin
gbk_chinese_ci
(default)
sjis
(Shift-JIS Japanese) collations:
sjis_bin
sjis_japanese_ci
(default)
tis620
(TIS620 Thai) collations:
tis620_bin
tis620_thai_ci
(default)
ujis
(EUC-JP Japanese) collations:
ujis_bin
ujis_japanese_ci
(default)
Why is cp932
needed?
In MySQL, the sjis
character set
corresponds to the Shift_JIS
character set
defined by IANA, which supports JIS X0201 and JIS X0208
characters. (See
http://www.iana.org/assignments/character-sets.)
However, the meaning of “SHIFT JIS” as a
descriptive term has become very vague and it often includes
the extensions to Shift_JIS
that are
defined by various vendors.
For example, “SHIFT JIS” used in Japanese Windows
environments is a Microsoft extension of
Shift_JIS
and its exact name is
Microsoft Windows Codepage : 932
or
cp932
. In addition to the characters
supported by Shift_JIS
,
cp932
supports extension characters such as
NEC special characters, NEC selected — IBM extended
characters, and IBM extended characters.
Many Japanese users have experienced problems using these extension characters. These problems stem from the following factors:
MySQL automatically converts character sets.
Character sets are converted via Unicode
(ucs2
).
The sjis
character set does not support
the conversion of these extension characters.
There are several conversion rules from so-called “SHIFT JIS” to Unicode, and some characters are converted to Unicode differently depending on the conversion rule. MySQL supports only one of these rules (described later).
The MySQL cp932
character set is designed
to solve these problems. It is available as of MySQL 5.0.3.
Because MySQL supports character set conversion, it is
important to separate IANA Shift_JIS
and
cp932
into two different character sets
because they provide different conversion rules.
How does cp932
differ
from sjis
?
The cp932
character set differs from
sjis
in the following ways:
cp932
supports NEC special characters,
NEC selected — IBM extended characters, and IBM
selected characters.
Some cp932
characters have two
different code points, both of which convert to the same
Unicode code point. When converting from Unicode back to
cp932
, one of the code points must be
selected. For this “round trip conversion,”
the rule recommended by Microsoft is used. (See
http://support.microsoft.com/kb/170559/EN-US/.)
The conversion rule works like this:
If the character is in both JIS X 0208 and NEC special characters, use the code point of JIS X 0208.
If the character is in both NEC special characters and IBM selected characters, use the code point of NEC special characters.
If the character is in both IBM selected characters and NEC selected — IBM extended characters, use the code point of IBM extended characters.
The table shown at
http://www.microsoft.com/globaldev/reference/dbcs/932.htm
provides information about the Unicode values of
cp932
characters. For
cp932
table entries with characters
under which a four-digit number appears, the number
represents the corresponding Unicode
(ucs2
) encoding. For table entries with
an underlined two-digit value appears, there is a range of
cp932
character values that begin with
those two digits. Clicking such a table entry takes you to
a page that displays the Unicode value for each of the
cp932
characters that begin with those
digits.
The following links are of special interest. They correspond to the encodings for the following sets of characters:
NEC special characters:
http://www.microsoft.com/globaldev/reference/dbcs/932/932_87.htm
NEC selected — IBM extended characters:
http://www.microsoft.com/globaldev/reference/dbcs/932/932_ED.htm http://www.microsoft.com/globaldev/reference/dbcs/932/932_EE.htm
IBM selected characters:
http://www.microsoft.com/globaldev/reference/dbcs/932/932_FA.htm http://www.microsoft.com/globaldev/reference/dbcs/932/932_FB.htm http://www.microsoft.com/globaldev/reference/dbcs/932/932_FC.htm
Starting from version 5.0.3, cp932
supports conversion of user-defined characters in
combination with eucjpms
, and solves
the problems with
sjis
/ujis
conversion. For details, please refer to
http://www.opengroup.or.jp/jvc/cde/sjis-euc-e.html.
For some characters, conversion to and from
ucs2
is different for
sjis
and cp932
. The
following tables illustrate these differences.
Conversion to ucs2
:
sjis /cp932
Value | sjis ->
ucs2 Conversion | cp932 ->
ucs2 Conversion |
5C | 005C | 005C |
7E | 007E | 007E |
815C | 2015 | 2015 |
815F | 005C | FF3C |
8160 | 301C | FF5E |
8161 | 2016 | 2225 |
817C | 2212 | FF0D |
8191 | 00A2 | FFE0 |
8192 | 00A3 | FFE1 |
81CA | 00AC | FFE2 |
Conversion from ucs2
:
ucs2 value | ucs2 ->
sjis Conversion | ucs2 ->
cp932 Conversion |
005C | 815F | 5C |
007E | 7E | 7E |
00A2 | 8191 | 3F |
00A3 | 8192 | 3F |
00AC | 81CA | 3F |
2015 | 815C | 815C |
2016 | 8161 | 3F |
2212 | 817C | 3F |
2225 | 3F | 8161 |
301C | 8160 | 3F |
FF0D | 3F | 817C |
FF3C | 3F | 815F |
FF5E | 3F | 8160 |
FFE0 | 3F | 8191 |
FFE1 | 3F | 8192 |
FFE2 | 3F | 81CA |
Users of any Japanese character sets should be aware that
using --character-set-client-handshake
(or
--skip-character-set-client-handshake
) has an
important effect. See Section 5.2.1, “mysqld Command Options”.