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The ASCII 26 character can be encoded as \Z  to enable you to work around the problem that ASCII 26 stands for END-OF-FILE on Windows. ASCII 26 within a file causes problems if you try to use mysql db_name  < file_name . 

The \%  and \_  sequences are used to search for literal instances of %  and _  in pattern-matching contexts where they would otherwise be interpreted as wildcard characters. See the description of the LIKE operator in Section 12.8.1, “String Comparison Functions and Operators” . If you use \%  or \_  outside of pattern-matching contexts, they evaluate to the strings \%  and \_ , not to %  and _ . 

There are several ways to include quote characters within a string: 

•A ’  inside a string quoted with ’  may be written as ’’ . 

•A "  inside a string quoted with "  may be written as "" . 

•Precede the quote character by an escape character ( \ ). 

•A ’  inside a string quoted with "  needs no special treatment and need not be doubled or escaped. In the same way, "  inside a string quoted with ’  needs no special treatment. 

The following SELECT  statements demonstrate how quoting and escaping work: 

mysql> SELECT ’hello’, ’"hello"’, ’""hello""’, ’hel’’lo’, ’\’hello’; +-------+---------+-----------+--------+--------+ | hello | "hello" | ""hello"" | hel’lo | ’hello | +-------+---------+-----------+--------+--------+ mysql> SELECT "hello", "’hello’", "’’hello’’", "hel""lo", ""hello"; +-------+---------+-----------+--------+--------+ | hello | ’hello’ | ’’hello’’ | hel"lo | "hello | +-------+---------+-----------+--------+--------+ mysql> SELECT ’This
Is
Four
Lines’; +--------------------+ | This Is Four Lines | +--------------------+ mysql> SELECT ’disappearing\ backslash’; +------------------------+ | disappearing backslash | +------------------------+ 

