Why is my MySQL LIKE operator case-sensitive even though my table uses utf8_general_ci?

Understanding Case-Sensitivity in MySQL

Your MySQL query using LIKE operator seems to exhibit case-sensitivity, despite your table being encoded as utf8_general_ci with MyISAM storage engine. This behavior can be puzzling, and understanding the underlying cause is crucial for resolving the issue.

Binary vs. Non-Binary String Comparison:

The key to understanding this behavior lies in the distinction between binary and non-binary string comparison. By default, MySQL performs non-binary string comparison, which is case-sensitive for most character sets, including utf8_general_ci.

Fixing Case-Sensitivity with Binary Comparison:

To resolve the case sensitivity issue, you can modify your query to use binary string comparison. This is achieved by prefixing the right-hand operand of the LIKE operator with the BINARY keyword. The corrected query would look like:

SELECT concat_ws(title,description) as concatenated HAVING concatenated LIKE BINARY '%SearchTerm%';

This modification forces MySQL to use binary string comparison, which is case-insensitive.

Alternative Solution Using COLLATE:

An alternative approach to achieve case-insensitive string comparison is to use the COLLATE clause. The COLLATE clause specifies the character set and collation rules to be applied to the string comparison. By specifying the utf8_bin collation, you can force MySQL to use binary string comparison. The query using COLLATE would be:

SELECT ....
FROM ....
WHERE `concatenated` LIKE '%SearchTerm%' COLLATE utf8_bin;

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