MySQL LIKE and Pattern Matching

How it works

LIKE uses percent for any length of text and underscore for one character. It is useful for simple patterns, but the column’s collation affects case and accent comparisons. This lab uses a known utf8mb4 collation. The example finds names ending with a word fragment, then uses an explicit binary collation for a case-sensitive comparison. A literal percent in user input needs escaping if it should not act as a wildcard.

Run in a disposable MySQL lab

Use Oracle MySQL 8.4 with InnoDB, not Bhylu’s SQLite playground. The examples were reviewed on MySQL 8.4.8. XAMPP may provide MariaDB, which has different feature and collation behaviour. Check your actual server before running the script. These lessons do not require a change to Bhylu’s PHP, Apache or normal database service.

1. On a separate lab instance, create the empty bhylu_mysql_lab schema. Stop if it already exists; do not overwrite an existing database.
2. Select that schema and import the complete repair-parts seed once. It sets the documented session mode, utf8mb4 collation, UTC and English date-name locale.
3. Run this lesson in a fresh copy of the seed, not after another lesson’s writes. Use the command-line client or a compatible editor. DELIMITER lines are client instructions for stored-program examples.

Download this complete lesson script. Its setup is the linked seed; review the dataset before changing it. Administrative and destructive examples are restricted to the specifically named disposable objects. Every script repeats the session settings because each new connection has its own session. No MySQL browser runner is currently available.

Example

SET NAMES utf8mb4 COLLATE utf8mb4_0900_ai_ci;
SET SESSION sql_mode = 'STRICT_TRANS_TABLES,ONLY_FULL_GROUP_BY,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION';
SET SESSION time_zone = '+00:00';
SET SESSION lc_time_names = 'en_US';
SELECT id, name
FROM parts
WHERE name LIKE '%cord'
ORDER BY id;
SELECT 'Patch' COLLATE utf8mb4_0900_bin LIKE 'patch' AS exact_case;

Expected result

3 | Cotton cord
0

Cotton cord matches the suffix pattern, while the binary-collation comparison does not equate the two cases. A leading wildcard usually prevents an ordinary B-tree prefix lookup; do not promise efficient full-text search from it. Choose equality, prefix matching or a dedicated search feature according to the actual user need, and explain the comparison policy consistently.