merge syntax in sql server code example

Example 1: t-sql merge example

MERGE sales.category t 
    USING sales.category_staging s
ON (s.category_id = t.category_id)
WHEN MATCHED
    THEN UPDATE SET 
        t.category_name = s.category_name,
        t.amount = s.amount
WHEN NOT MATCHED BY TARGET 
    THEN INSERT (category_id, category_name, amount)
         VALUES (s.category_id, s.category_name, s.amount)
WHEN NOT MATCHED BY SOURCE 
    THEN DELETE;

Example 2: sql merge statement

MERGE LoginTypes T
        USING (SELECT 'System' as Description) S
        ON(S.Description = T.Description)
WHEN NOT MATCHED BY TARGET
    THEN INSERT(Description, CreatedTimestamp, LastUpdatedTimestamp)
VALUES('System', getdate(), getdate());