Mysql Literal(文字)

字符串

单引号,双引号都可以表示字符
sql 'a string' "another string"

转义字符

Escape Sequence	Character Represented by Sequence
\0	An ASCII NUL (X’00’) character
’	A single quote (’) character
"	A double quote (") character
\b	A backspace character
\n	A newline (linefeed) character
\r	A carriage return character
\t	A tab character
\Z	ASCII 26 (Control+Z); see note following the table
\	A backslash () character
%	A % character; see note following the table
_	A _ character; see note following the table

例子

SELECT 'hello', '"hello"', '""hello""', 'hel''lo', '\'hello'; 语句中包含引号
SELECT "hello", "'hello'", "''hello''", "hel""lo", "\"hello"; 语句中包含引号
SELECT 'This\nIs\nFour\nLines';

数字

时间

十六进制

二进制

布尔

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参考:
https://dev.mysql.com/doc/refman/8.0/en/literals.html