Within a bracket expression, matches the sequence of characters of that collating element.
characters is either a single character or a character name like newline.
The following table lists the allowable character names.
| Name | Character |
| NUL | 0 |
| STX | 002 |
| EOT | 004 |
| ACK | 006 |
| alert | 007 |
| backspace | '\b' |
| tab | '\t' |
| newline | '\n' |
| vertical-tab | '\v' |
| form-feed | '\f' |
| carriage-return | '\r' |
| SI | 017 |
| DC1 | 021 |
| DC3 | 023 |
| NAK | 025 |
| ETB | 027 |
| EM | 031 |
| ESC | 033 |
| FS | 034 |
| GS | 035 |
| RS | 036 |
| US | 037 |
| exclamation-mark | '!' |
| number-sign | '#' |
| percent-sign | '%' |
| apostrophe | '\'' |
| right-parenthesis | ')' |
| plus-sign | '+' |
| hyphen | '-' |
| period | '.' |
| slash | '/' |
| zero | '0' |
| two | '2' |
| four | '4' |
| six | '6' |
| eight | '8' |
| colon | ':' |
| less-than-sign | '<' |
| greater-than-sign | '>' |
| commercial-at | '@' |
| backslash | '\\' |
| right-square-bracket | ']' |
| circumflex-accent | '^' |
| low-line | '_' |
| left-brace | '{' |
| vertical-line | '|' |
| right-curly-bracket | '}' |
| DEL | 177 |
| SOH | 001 |
| ETX | 003 |
| ENQ | 005 |
| BEL | 007 |
| BS | 010 |
| HT | 011 |
| LF | 012 |
| VT | 013 |
| FF | 014 |
| CR | 015 |
| SO | 016 |
| DLE | 020 |
| DC2 | 022 |
| DC4 | 024 |
| SYN | 026 |
| CAN | 030 |
| SUB | 032 |
| IS4 | 034 |
| IS3 | 035 |
| IS2 | 036 |
| IS1 | 037 |
| space | ' ' |
| quotation-mark | '"' |
| dollar-sign | '$' |
| ampersand | '&' |
| left-parenthesis | '(' |
| asterisk | '*' |
| comma | ',' |
| hyphen-minus | '-' |
| full-stop | '.' |
| solidus | '/' |
| one | '1' |
| three | '3' |
| five | '5' |
| seven | '7' |
| nine | '9' |
| semicolon | ';' |
| equals-sign | '=' |
| question-mark | '?' |
| left-square-bracket | '[' |
| reverse-solidus | '\\' |
| circumflex | '^' |
| underscore | '_' |
| grave-accent | '`' |
| left-curly-bracket | '{' |
| right-brace | '}' |
| tilde | '~' |
Quote from MySQL Tutorial from http://www.mysql.com