How Can I Achieve MySQL's ON DUPLICATE KEY UPDATE Functionality in SQL Server?

SQL Server Alternative to MySQL's ON DUPLICATE KEY UPDATE

In MySQL, the ON DUPLICATE KEY UPDATE clause allows users to specify that a row should be updated if a duplicate key constraint is violated. This functionality enables efficient handling of duplicate key scenarios in data manipulation operations.

SQL Server provides a similar mechanism to achieve this behavior through the MERGE statement. The MERGE statement allows users to perform a combination of INSERT, UPDATE, and DELETE operations based on match criteria between two tables.

For example, to simulate the behavior of ON DUPLICATE KEY UPDATE in SQL Server, consider the following MERGE statement:

MERGE
INTO MyTable AS target
USING (SELECT id, value FROM NewData) AS source
ON (target.id = source.id)
WHEN MATCHED
  THEN UPDATE SET value = source.value
WHEN NOT MATCHED
  THEN INSERT (id, value) VALUES (source.id, source.value);

In this statement, the MERGE operation first checks whether a row with the specified ID (id) already exists in the target table (MyTable). If a matching row is found, the value is updated with the value from the source table (NewData). If no matching row is found, a new row is inserted.

By utilizing the MERGE statement, SQL Server provides an efficient and versatile alternative to MySQL's ON DUPLICATE KEY UPDATE clause. It allows developers to handle duplicate key scenarios with ease and flexibility in their data manipulation operations.

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