All that DB2 does is to allow an UPDATE, DELETE, and INSERT to appear in the from clause of a select and allow the user to chose which transition table shall be selected from.

DB 2所做的就是允许UPDATE、DELETE和INSERT出现在选择语句的from子句中，并允许用户选择应该从哪个过渡表进行选择。

youdao

"If they decide that everyone needs to eat broccoli, " then the commerce clause could allow Congress to require everyone to buy a certain quantity of broccoli, the judge said.

WSJ: States Ask Judge to Throw Out Health Law

The power in this clause is therefore required so that the law can be changed to allow the Church in Wales to marry same sex couples (if it were to resolve to allow it), without the need for primary legislation.

BBC: The Church in Wales and same-sex marriage

The commerce clause has been interpreted to allow Congress to regulate virtually any economic activity, under the theory that it affects interstate commerce.

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