The percent sign % in MySQL is a wildcard character that can match any sequence of characters. It can be used for: 1. String matching (such as: LIKE '%string%'); 2. Range query (such as: BETWEEN '%start%' AND '%end%'); 3. Regular expression matching (such as: REGEXP '%.*%'); Note: % matches any character sequence, but cannot match the empty string; it cannot appear at the beginning or end of a wildcard expression; to match an actual percent sign, the escape character \ needs to be used.
The percent sign (%) in MySQL
The percent sign (%) in MySQL is a Wildcard, used to match any sequence of characters. It can be used in the following scenarios:
1. String matching
In the LIKE clause, % can be used to match any sequence of characters:
SELECT * FROM table_name WHERE column_name LIKE '%string%';
This will match any record containing the string "string".
2. Range query
In the BETWEEN clause, % can be used to specify the left or right boundary of the range:
SELECT * FROM table_name WHERE column_name BETWEEN '%start%' AND '%end%';
This will match Records with column_name values between "start" and "end" (including "start" and "end" themselves).
3. Regular expression
In the REGEXP clause, % can be used as a wildcard to match any character:
SELECT * FROM table_name WHERE column_name REGEXP '%.*%';
This will match the A record of any sequence of characters.
Note:
- % matches any sequence of characters, but cannot match the empty string.
- % cannot appear at the beginning or end of a wildcard expression.
- To match the actual percent sign, you need to use the escape character \, such as \%.
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