乐观锁

错误，乐观锁是写写控制，MVCC是写读控制

亦可使用乐观锁

Anthony McMahon The piece you wrote about Ken is pretty interesting. You dove right into Ken’s background which provided some vital information to the viewer. The background information stated the family structure in Ken’s life which is a really important detail when describing a character. I think many things within the paper should be explained a little more thoroughly or with greater detail. Like how flunking out of his college shaped him into who he is now, or how studying hard for his ACT impacted his work ethic in the future. Just some ideas, but definitely more depth is needed to truly recognize Ken deeper. As for sentence structure, your main body paragraph can be broken down into a couple of separate paragraphs. Most of the paper was written chronologically which is okay, but try to separate the one big paragraph into a couple smaller ones. Try starting by taking the first couple sentences, forge them into an introduction, which you did, and then dive into each paragraph chronically. As an example, you can talk about high school in the second paragraph, flunking college in the third, nursing school in the fourth, and so on. But within these paragraph’s try adding some transitions so it flows a little better. The last thing I got to say is, start talking about the mask he wears at work in front of the patients vs. unmasked at home, earlier in your paragraph. The reader practically reads an autobiography of Ken for 1100 words to just get a couple sentences at the end about who he really is. Remember that it’s a profile about who Ken is under the mask, not so much of his life story.