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CREATE TABLE products (`key` VARCHAR(255) PRIMARY KEY, cost INT);
INSERT INTO products VALUES ('a', 5), ('c', 6);
SELECT * FROM products;
Records: 2 Duplicates: 0 Warnings: 0
| key | cost |
|---|---|
| a | 5 |
| c | 6 |
INSERT INTO products
SELECT updates.key, updates.cost
FROM (
VALUES
ROW ('a', 10),
ROW ('c', 3),
ROW ('foo', 8)
) AS updates (`key`, cost)
ON DUPLICATE KEY
UPDATE products.cost = products.cost + updates.cost;
SELECT * FROM products;
Records: 3 Duplicates: 2 Warnings: 0
| key | cost |
|---|---|
| a | 15 |
| c | 9 |
| foo | 8 |