Efficiently Handling Multiple Rows with MySQL's ON DUPLICATE KEY UPDATE
MySQL offers a streamlined approach to managing multiple row insertions while simultaneously checking for and updating existing unique values. This is accomplished using the ON DUPLICATE KEY UPDATE
clause. This feature allows for conditional updates or insertions of specific fields within a single query.
To selectively update existing rows and add new ones, leverage an alias or the VALUES
keyword in conjunction with ON DUPLICATE KEY UPDATE
.
MySQL 8.0.19 and later (Using an Alias):
INSERT INTO beautiful (name, age) VALUES ('Helen', 24), ('Katrina', 21), ('Samia', 22), ('Hui Ling', 25), ('Yumie', 29) AS new ON DUPLICATE KEY UPDATE age = new.age
MySQL 8.0.19 and earlier (Using the VALUES Keyword):
INSERT INTO beautiful (name, age) VALUES ('Helen', 24), ('Katrina', 21), ('Samia', 22), ('Hui Ling', 25), ('Yumie', 29) ON DUPLICATE KEY UPDATE age = VALUES(age)
These examples demonstrate how to update or insert data based on existing unique keys. If a unique key already exists, the specified fields are updated; otherwise, a new row is inserted. The VALUES
keyword or the alias new
references the values being inserted in the INSERT
statement.
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