How to use escape in mysql

The ESCAPE keyword is used to specify escape characters to escape special characters in a string to prevent them from being recognized as metacharacters or delimiters. It immediately precedes the escaped string, using the format: ESCAPE 'escape character'. By default, ESCAPE escapes backslashes, percent signs, underscores, single quotes, double quotes, backtick marks, spaces, tabs, newlines, and carriage returns.

Detailed explanation of ESCAPE usage in MySQL

The ESCAPE keyword is used to specify escape characters, used in strings Escape special characters. It prevents special characters from being recognized as metacharacters or delimiters.

Usage:

ESCAPE 'Escape character'

Among them, 'Escape character' is a valid single Character escape character, representing the character used to escape special characters.

Example:

Suppose we have a string: "Hello, \"World\"!". If we do not use ESCAPE, then the double quotes (") will be recognized as string delimiters by MySQL, causing an error. To solve this problem, we can use the ESCAPE character:

<code>mysql> SELECT 'Hello, \"World\"!' ESCAPE '\';
+---------------------------------+
| Hello, "World"!                 |
+---------------------------------+</code>

In this example, we use Backslash () is used as an escape character, specified by ESCAPE '\'. In this way, the double quotation mark before the backslash is escaped and recognized as an ordinary character instead of a string delimiter.

Special characters:

By default, ESCAPE will escape the following special characters:

• Backslash()
• Percent sign (%)
• Underscore (_)
• Single quote (')
• Double quote (")
• Backtick ( `)
• Space ( )
• Tab (\t)
• Line feed (\n)
• Carriage return (\r)

Note:

• The ESCAPE keyword must immediately precede the escaped string.
• The escape character must be a single character.
• Escape characters can only be used once in the escaped string.

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