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From Clinton Begin <clinton.be...@gmail.com>
Subject Re: Locks
Date Wed, 14 Apr 2010 16:51:52 GMT
Not in iBATIS 2... unless you override the entire transaction API.

On Wed, Apr 14, 2010 at 10:43 AM, Ejaz X Mohammed <
ejaz.mohammed@jpmorgan.com> wrote:

> I changed the code to use plain jdbc instead of ibatis ... as I said I'm
> doing just SELECT ... I started no tranasaction .. now I don't see any
> locks, perf seems to be better too ...
>
> If we start a transaction, sybase takes locks ... read lock for SELECT ...
>
> Can we avoid starting TX during select in ibatis?
>
> Ejaz
>
>
> -----Original Message-----
> From: Jeff Butler [mailto:jeffgbutler@gmail.com]
> Sent: Wednesday, April 14, 2010 11:36 AM
> To: user-java@ibatis.apache.org
> Subject: Re: Locks
>
> I assume you're using SIMPLE datasource.  With that data source, the
> isolation level is set as a driver default.  I just did a quick test
> with HSQLDB and the default seems to be TRANSACTION_READ_COMMITTED - a
> middle of the road isolation level.  Maybe there is some setting on
> the Sybase driver that will allow you to change the default isolation
> level?
>
> Alternatively, you can do it in code like this:
>
> try {
>  sqlMapClient.startTransaction(Connection.TRANSACTION_READ_UNCOMMITTED);
>
>  -- do some work
> } finally {
>  sqlMapClient.endTransaction();
> }
>
> If you are using some other datasource (like JNDI), then you'll need
> to look to that datasource for information about changing the
> isolation level.
>
> Jeff Butler
>
>
>
>
>
> On Wed, Apr 14, 2010 at 9:51 AM, Ejaz X Mohammed
> <ejaz.mohammed@jpmorgan.com> wrote:
> > These are my settings ...
> >
> >    <!--
> >    These settings control SqlMap configuration details, primarily to do
> with transaction
> >    management. They are all optional (see the Developer Guide for more).
> >    -->
> >    <settings
> >            cacheModelsEnabled="true"
> >            enhancementEnabled="true"
> >            lazyLoadingEnabled="true"
> >            maxRequests="32"
> >            maxSessions="10"
> >            maxTransactions="5"
> >            useStatementNamespaces="true"
> >        />
> >
> >    <!--
> >    Configure a datasource to use with this SQL Map using
> SimpleDataSource.
> >    Notice the use of the properties from the above resource
> >    -->
> >    <transactionManager type="JDBC" >
> >        <dataSource type="....">
> >            <property name="JDBC.Driver" value="${jdbc.driver}"/>
> >            <property name="JDBC.ConnectionURL" value="${jdbc.url}"/>
> >            <property name="JDBC.Username" value="${jdbc.user}"/>
> >            <property name="JDBC.Password" value="${jdbc.password}"/>
> >            <property name="JDBC.DefaultAutoCommit" value="true"/>
> >        </dataSource>
> >    </transactionManager>
> >
> >
> >
> >
> > -----Original Message-----
> > From: Jeff Butler [mailto:jeffgbutler@gmail.com]
> > Sent: Wednesday, April 14, 2010 9:44 AM
> > To: user-java@ibatis.apache.org
> > Subject: Re: Locks
> >
> > It's dependent on the transaction isolation level set on your
> > connection.  There are many variables involved - what is your
> > environment (POOLED, UNPOOLED, JNDI, etc.)?
> >
> > Jeff Butler
> >
> >
> > On Wed, Apr 14, 2010 at 9:38 AM, Ejaz X Mohammed
> > <ejaz.mohammed@jpmorgan.com> wrote:
> >> Hello,
> >>
> >>
> >>
> >> I have an application running on Sybase. DBAs tell me that it is
> generating
> >> too many locks ... I know that all I'm doing is SELECT.
> >>
> >>
> >>
> >> I'm not sure how SELECT can create locks in database.
> >>
> >>
> >>
> >> Any suggestions ?
> >>
> >>
> >>
> >> Thanks
> >>
> >> Ejaz
> >>
> >> This email is confidential and subject to important disclaimers and
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> >
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> >
>
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