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MySQL – Character Set

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The MySQL Character Set

The MySQL Character set is used to determine the set of permissible characters within a string. It allows for the storage of data in various character encodings. By default, MySQL uses the “utf8mb4” character set.

These character sets provides several functionalities −

  • Storage Variety − MySQL allows the storage of strings in various character sets.
  • String Comparison − Collations help in comparing strings based on the chosen character set.
  • Mixed Character Sets − It is possible to combine strings with different character sets or collations within the same server, database, or table.
  • Specifying Character Set and Collation − You can define the character set and collation at different levels of the database structure.

The MySQL Show Character-Set

You can use the MySQL SHOW CHARACTER SET statement to view the list of all the available character sets.

Syntax

Following is the syntax of the SHOW CHARACTER SET statement −

SHOW CHARACTER SET [LIKE ''pattern'' | WHERE expr]

Example

The following query retrieves a list of available character sets, along with their descriptions, default collations, and maximum lengths in a MySQL database −

SHOW CHARACTER SET;

Output

Following is the output obtained −

Charset Description Default collation Maxlen
armscii8 ARMSCII-8 Armenian armscii8_general_ci 1
ascii US ASCII ascii_general_ci 1
big5 Big5 Traditional Chinese big5_chinese_ci 2
binary Binary pseudo charset binary 1
cp1250 Windows Central European cp1250_general_ci 1
cp1251 Windows Cyrillic cp1251_general_ci 1
cp1256 Windows Arabic cp1256_general_ci 1
cp1257 Windows Baltic cp1257_general_ci 1
cp850 DOS West European cp850_general_ci 1
cp852 DOS Central European cp852_general_ci 1
cp866 DOS Russian cp866_general_ci 1
cp932 SJIS for Windows Japanese cp932_japanese_ci 2
dec8 DEC West European dec8_swedish_ci 1
eucjpms UJIS for Windows Japanese eucjpms_japanese_ci 3
euckr EUC-KR Korean euckr_korean_ci 2
gb18030 China National Standard GB18030 gb18030_chinese_ci 4
gb2312 GB2312 Simplified Chinese gb2312_chinese_ci 2
gbk GBK Simplified Chinese gbk_chinese_ci 2
geostd8 GEOSTD8 Georgian geostd8_general_ci 1
greek ISO 8859-7 Greek greek_general_ci 1
hebrew ISO 8859-8 Hebrew hebrew_general_ci 1
hp8 HP West European hp8_english_ci 1
keybcs2 DOS Kamenicky Czech-Slovak keybcs2_general_ci 1
koi8r KOI8-R Relcom Russian koi8r_general_ci 1
koi8u KOI8-U Ukrainian koi8u_general_ci 1
latin1 cp1252 West European latin1_swedish_ci 1
latin2 ISO 8859-2 Central European latin2_general_ci 1
latin5 ISO 8859-9 Turkish latin5_turkish_ci 1
latin7 ISO 8859-13 Baltic latin7_general_ci 1
macce Mac Central European macce_general_ci 1
macroman Mac West European macroman_general_ci 1
sjis Shift-JIS Japanese sjis_japanese_ci 2
swe7 7bit Swedish swe7_swedish_ci 1
tis620 TIS620 Thai tis620_thai_ci 1
ucs2 UCS-2 Unicode ucs2_general_ci 2
ujis EUC-JP Japanese ujis_japanese_ci 3
utf16 UTF-16 Unicode utf16_general_ci 4
utf16le UTF-16LE Unicode utf16le_general_ci 4
utf32 UTF-32 Unicode utf32_general_ci 4
utf8mb3 UTF-8 Unicode utf8mb3_general_ci 3
utf8mb4 UTF-8 Unicode utf8mb4_0900_ai_ci 4

The MySQL Set Character-set

The MySQL SET CHARACTER SET Statement is used to assign a value to the character set attribute. It maps all the strings between the server and the current client with the specified mapping set. This statement changes values of the “character_set_client” and “character_set_results” variables.

Syntax

Following is the syntax of the MySQL SET CHARACTER SET Statement −

SET {CHARACTER SET | CHARSET} {''charset_name'' | DEFAULT}

Where, ”charset_name” is the name of the character set.

Example

The query given below sets the character set to “macroman” −

SET CHARACTER SET macroman;

Output

The output produced is as shown below −

Query OK, 0 rows affected (0.10 sec)

Verification

You can verify the character set values using the SHOW VARIABLES LIKE statement as shown below −

SHOW VARIABLES LIKE "character_set_client";

Following is the output obtained −

Variable_name Value
character_set_client macroman

Now verifying the current value of the “character_set_results” variable −

SHOW VARIABLES LIKE "character_set_results";

The result produced is as shown below −

Variable_name Value
character_set_results macroman

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