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CREATE TABLE articles (id INT, image VARCHAR(255));
CREATE TABLE image_counter (id INT AUTO_INCREMENT PRIMARY KEY);
CREATE TRIGGER tr_name
BEFORE INSERT
ON articles
FOR EACH ROW
BEGIN
INSERT INTO image_counter VALUES (DEFAULT);
SET NEW.image = CONCAT('catalog/blog-image/', LAST_INSERT_ID(), '.jpg');
DELETE FROM image_counter;
END
INSERT INTO articles (id) VALUES (1);
SELECT * FROM articles;
| id | image |
|---|---|
| 1 | catalog/blog-image/1.jpg |
INSERT INTO articles (id) VALUES (2);
SELECT * FROM articles;
| id | image |
|---|---|
| 1 | catalog/blog-image/1.jpg |
| 2 | catalog/blog-image/2.jpg |
INSERT INTO articles (id) VALUES (3);
SELECT * FROM articles;
| id | image |
|---|---|
| 1 | catalog/blog-image/1.jpg |
| 2 | catalog/blog-image/2.jpg |
| 3 | catalog/blog-image/3.jpg |
SELECT * FROM image_counter;