sql - 在这种情况下如何使用 T-SQL MERGE？

Question

我是 T-SQL 命令的新手 MERGE所以我在我的 SQL 逻辑中找到了一个可以使用它并想测试它但不知道我应该如何使用它的地方:

IF (EXISTS (SELECT 1 FROM commissions_history WHERE request = @requestID))
    UPDATE commissions_history
    SET amount = @amount
    WHERE request = @requestID
ELSE
    INSERT INTO commissions_history (amount) VALUES @amount)

请建议正确的用法。谢谢!

Answer 1

你看帮助了吗？这是一个简单的例子:

MERGE dbo.commissions_history AS target
USING (SELECT @amount, @requestID) AS source (amount, request)
ON (target.request = source.request)
WHEN MATCHED THEN
    UPDATE SET amount = source.amount
WHEN NOT MATCHED THEN
    INSERT (request, amount)
    VALUES (source.request, source.amount);