In SQL, we have tables containing individual rows. Tables have strict schemas that every row must obey; there are columns with types and other possible constraints: unique, not null, value checks or references to rows of other tables. Referential integrity lies at the heart of this data approach - guarantee that if row B1 of table B references row A1 of table A, referred row (A1) must exist; orphan rows are not allowed. If we want to delete A1 row, there are two options:
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2004年，成立不足两年的魅族成为美国芯片公司Sigmatel全球最大的客户，Sigmatel特地派人亲临珠海，给魅族颁发了全球第一个Sigmatel3520芯片10万片纪念牌。20年后，压倒魅族的“最后一根稻草”也是芯片。。业内人士推荐同城约会作为进阶阅读
"It is with profound grief that we confirm the passing of Katherine Hartley Short," Martin Short's representative said in a statement to BBC News. "The Short family is devastated by this loss and asks for privacy at this time."，推荐阅读体育直播获取更多信息
task.internalWait(ms); // 阻塞等待