Documentation Home
MySQL 5.7 Reference Manual
Related Documentation Download this Manual
PDF (US Ltr) - 35.0Mb
PDF (A4) - 35.1Mb
Man Pages (TGZ) - 255.5Kb
Man Pages (Zip) - 360.4Kb
Info (Gzip) - 3.4Mb
Info (Zip) - 3.4Mb
Excerpts from this Manual

MySQL 5.7 Reference Manual  /  Character Sets, Collations, Unicode  /  Character Sets and Collations in MySQL

10.2 Character Sets and Collations in MySQL

MySQL Server supports multiple character sets. To display the available character sets, use the INFORMATION_SCHEMA CHARACTER_SETS table or the SHOW CHARACTER SET statement. A partial listing follows. For more complete information, see Section 10.10, “Supported Character Sets and Collations”.

mysql> SHOW CHARACTER SET;
+----------+---------------------------------+---------------------+--------+
| Charset  | Description                     | Default collation   | Maxlen |
+----------+---------------------------------+---------------------+--------+
| big5     | Big5 Traditional Chinese        | big5_chinese_ci     |      2 |
...
| latin1   | cp1252 West European            | latin1_swedish_ci   |      1 |
| latin2   | ISO 8859-2 Central European     | latin2_general_ci   |      1 |
...
| utf8     | UTF-8 Unicode                   | utf8_general_ci     |      3 |
| ucs2     | UCS-2 Unicode                   | ucs2_general_ci     |      2 |
...
| utf8mb4  | UTF-8 Unicode                   | utf8mb4_general_ci  |      4 |
...
| binary   | Binary pseudo charset           | binary              |      1 |
...

By default, the SHOW CHARACTER SET statement displays all available character sets. It takes an optional LIKE or WHERE clause that indicates which character set names to match. For example:

mysql> SHOW CHARACTER SET LIKE 'latin%';
+---------+-----------------------------+-------------------+--------+
| Charset | Description                 | Default collation | Maxlen |
+---------+-----------------------------+-------------------+--------+
| 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 |
+---------+-----------------------------+-------------------+--------+

A given character set always has at least one collation, and most character sets have several. To list the display collations for a character set, use the INFORMATION_SCHEMA COLLATIONS table or the SHOW COLLATION statement.

By default, the SHOW COLLATION statement displays all available collations. It takes an optional LIKE or WHERE clause that indicates which collation names to display. For example, to see the collations for the default character set, latin1 (cp1252 West European), use this statement:

mysql> SHOW COLLATION WHERE Charset = 'latin1';
+-------------------+---------+----+---------+----------+---------+
| Collation         | Charset | Id | Default | Compiled | Sortlen |
+-------------------+---------+----+---------+----------+---------+
| latin1_german1_ci | latin1  |  5 |         | Yes      |       1 |
| latin1_swedish_ci | latin1  |  8 | Yes     | Yes      |       1 |
| latin1_danish_ci  | latin1  | 15 |         | Yes      |       1 |
| latin1_german2_ci | latin1  | 31 |         | Yes      |       2 |
| latin1_bin        | latin1  | 47 |         | Yes      |       1 |
| latin1_general_ci | latin1  | 48 |         | Yes      |       1 |
| latin1_general_cs | latin1  | 49 |         | Yes      |       1 |
| latin1_spanish_ci | latin1  | 94 |         | Yes      |       1 |
+-------------------+---------+----+---------+----------+---------+

The latin1 collations have the following meanings.

Collation Meaning
latin1_bin Binary according to latin1 encoding
latin1_danish_ci Danish/Norwegian
latin1_general_ci Multilingual (Western European)
latin1_general_cs Multilingual (ISO Western European), case-sensitive
latin1_german1_ci German DIN-1 (dictionary order)
latin1_german2_ci German DIN-2 (phone book order)
latin1_spanish_ci Modern Spanish
latin1_swedish_ci Swedish/Finnish

Collations have these general characteristics:

  • Two different character sets cannot have the same collation.

  • Each character set has a default collation. For example, the default collations for latin1 and utf8 are latin1_swedish_ci and utf8_general_ci, respectively. The INFORMATION_SCHEMA CHARACTER_SETS table and the SHOW CHARACTER SET statement indicate the default collation for each character set. The INFORMATION_SCHEMA COLLATIONS table and the SHOW COLLATION statement have a column that indicates for each collation whether it is the default for its character set (Yes if so, empty if not).

  • Collation names start with the name of the character set with which they are associated, generally followed by one or more suffixes indicating other collation characteristics. For additional information about naming conventions, see Section 10.3.1, “Collation Naming Conventions”.

When a character set has multiple collations, it might not be clear which collation is most suitable for a given application. To avoid choosing an inappropriate collation, perform some comparisons with representative data values to make sure that a given collation sorts values the way you expect.