MySQL follows only one version of the JIS (Japanese Industrial Standards) standard description. In MySQL, 5C  is always the reverse solidus ( \ ) . 

A.11.7. Of what issues should I be aware when working with Korean character sets in MySQL? 

In theory, while there have been several versions of the euckr  ( Extended Unix Code Korea ) character set, only one problem has been noted. We use the “ASCII”  variant of EUC-KR, in which the code point 0x5c  is REVERSE SOLIDUS, that is \ , instead of the “KS-Roman”  variant of EUC- KR, in which the code point 0x5c  is WON SIGN  ( ₩ ). This means that you cannot convert Unicode U +20A9  to euckr : 

A.11.8. Why do I get Incorrect string value  error messages? 

mysql> SELECT CONVERT(’ ₩ ’ USING euckr) AS euckr, HEX(CONVERT(’ ₩ ’ USING euckr)) AS hexeuckr; +-------+----------+ | euckr | hexeuckr | +-------+----------+ | ? | 3F | +-------+----------+ 

To see the problem, create a table with one Unicode ( ucs2 ) column and one Chinese ( gb2312 ) column. 

mysql> CREATE TABLE ch (ucs2 CHAR(3) CHARACTER SET ucs2, gb2312 CHAR(3) CHARACTER SET gb2312); 

In nonstrict SQL mode, try to place the rare character 汌  in both columns. 

mysql> SET sql_mode = ’’; mysql> INSERT INTO ch VALUES (’A 汌 B’,’A 汌 B’); Query OK, 1 row affected, 1 warning (0.00 sec) 

The INSERT  produces a warning. Use the following statement to see what it is: 

mysql> SHOW WARNINGS\G *************************** 1. row *************************** Level: Warning Code: 1366 Message: Incorrect string value: ’\xE6\xB1\x8CB’ for column ’gb2312’ at row 1 

So it is a warning about the gb2312  column only. 

mysql> SELECT ucs2,HEX(ucs2),gb2312,HEX(gb2312) FROM ch; +-------+--------------+--------+-------------+ | ucs2 | HEX(ucs2) | gb2312 | HEX(gb2312) | +-------+--------------+--------+-------------+ | A 汌 B | 00416C4C0042 | A?B | 413F42 | +-------+--------------+--------+-------------+ 

Several things need explanation here: 

1. The 汌  character is not in the gb2312  character set, as described earlier. 

2. If you are using an old version of MySQL, you may see a different message. 

3. A warning occurs rather than an error because MySQL is not set to use strict SQL mode. In nonstrict mode, MySQL tries to do what it can, to get the best fit, rather than give up. With 

