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    1. POAny way to select without causing locking in MySQL?
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    1. COI know this post is old, but this answer is too general, and is only sometimes true. See http://dev.mysql.com/doc/refman/5.0/en/innodb-locks-set.html. Locks most certainly _are_ acquired for reads, depending on the isolation level. Specifically, in this case, the poster is dealing with replicated databases and stated explicitly that he can use `show processlist` to actually see the locks. So it is safe to assume that there are in fact locks being taken.
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    2. COThe answer is always true. There is of course, some locking - some internal mutexes inside innodb which are used (innodb buffer pool mutex, for example). Most users don't care about or notice these locks and they normally only contended during DDL operations (such as if you have a 16G buffer pool and do "drop table" in another thread). But it doesn't take any row-locks by default. That's what I meant. The answer was quite vague though.
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    3. CO_Always_ always? What if the transaction isolation level is set to serializable, or the select statement uses LOCK IN SHARE MODE and autocommit is disabled? I know many (most/all?) database servers now use snapshot isolation by default instead of true serialization, but aren't there still occasional justifications for forcing serializable reads? But it sounds like you were saying that in all remotely normal cases, the default conditions in MySQL do not cause read locks that affect other threads, so don't worry about a problem you don't have? I tried to undo my downvote, BTW. Sorry...
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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