Re: is a MySQL write lock automatically released when a pooled connection is closed?

From:

=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 09 Mar 2008 21:51:48 -0400

Message-ID:

<47d4942d$0$90276$14726298@news.sunsite.dk>

christopher@dailycrossword.com wrote:

On Mar 7, 2:29 pm, christop...@dailycrossword.com wrote:

Greetings,
I am using JDBC (probably version 2), and I use code like this to open
and close connections:

I have examined the source for the pooled connection's close() method,
and it simply returns the connection object to a generic pool (Jakarta
commons DBCP and Pool), so it seems as though no reset is ever done to
release locks or close temporary tables, etc., as is is in other
pooled connectors. I have read a number of posts from several years
ago either asking the same question, or declaring that 'table locks'
should never be used in 'robust applications'. I am very concerned
that an uncaught exception or transient network failure would lock the
table indefinitely.

For what it's worth I am re-designing that portion of the application
to produce meaningful (if a little stale) data without using the table
locks.

LOCK TABLE is a hack. A hack that does not fit well with Java.

InnoDB tables, transactions and a suitable transaction isolation
level.

Arne

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