hibernate的配置文件属性:connection.autocommit=true有哪些缺点?为何不建议使用true呢????

meadking 2008-08-05 06:30:04
hibernate的配置文件属性:connection.autocommit=true有哪些缺点?为何不建议使用true呢????
谢谢!
是不是这样就没有使用缓存啦?
用spring+hibenrate的HibernateTemplate,要使用事务,否则就设定connection.autocommit=true
呵呵!
...全文
4073 12 打赏 收藏 转发到动态 举报
AI 作业
写回复
用AI写文章
12 条回复
切换为时间正序
请发表友善的回复…
发表回复
天下五折 2011-09-16
  • 打赏
  • 举报
 回复
茅塞顿开
A9112003 2010-12-30
  • 打赏
  • 举报
 回复
看完奥运会，直接无语掉了，总结呢？你的承诺呢，你的代价呢？
meadking 2008-08-24
  • 打赏
  • 举报
 回复
非常感谢!sunyujia
呵呵!
Mead
sunyujia 2008-08-08
  • 打赏
  • 举报
 回复
呵呵,全部疑惑都已经解开,包括spring为什么在事务块设置为AUTO,flush()在事务块中也是十分有意义的,尽管commit时候是统一提交但是,hibernate是会记录逻辑顺序,而且在事务块中设置AUTO是十分严谨的.因为NEVER时commit会进行智能判断等等,看完奥运后我会在博客中进行总结.
sunyujia 2008-08-08
  • 打赏
  • 举报
 回复
这个问题很有讨论的价值
无论connection.autocommit=true还是connection.autocommit=false 无论是声明式事务还是编程式事务都是有效的(即SuperA方法中的suba方法成功,subb方法失败,是会回滚掉suba的)
这个只是设置conn默认值而已.

我不知道为什么不建议使用true.官方有说明吗?
但是我分别说说使用true和不使用true的问题
(一)如果默认为true
1.保存对象是不需要开事务的,读写随意.
2.session.flush()是有意义的,因为session.flush()的操作是可以生效的.
(二)如果默认值为false
1.保存对象必须使用事务,不管是声明式事务还是编程式事务.当然也可以采用重置autocommit的方式
2.session.flush()是在事务块里面是没有意义的,因为数据操作是要统一提交的,但是这里我并没用经过复杂的测试,稍后有时间我再尝试几种情况.
3.如果不在事务块内修改持久化对象后执行session.flush(),数据库会锁表.

总结:
session的autocommit模式也是可以修改的,所以默认为false,在复杂的情况下需要手工控制flush时可以修改autocommit

疑惑:
查阅了spring的源码,在使用spring的声明式事务时,会修改session的FlushMode为AUTO,很不解,查阅JDBCTransaction类的commit方法
if ( !transactionContext.isFlushModeNever() && callback ) {

transactionContext.managedFlush(); //if an exception occurs during flush, user must call rollback()

}

实际上当FlushMode为MANUAL或NEVER时,提交的时候会通过managedFlush()遍历所有的session的flush方法,不知道在事务块里面spring为什么要修改FlushMode为AUTO,当事务结束时又会改回原有的mode.
楼下可以继续讨论.
f3135210 2008-08-06
  • 打赏
  • 举报
 回复



路过`` 帮顶`````
meadking 2008-08-06
  • 打赏
  • 举报
 回复
恩，非常感谢！这样设置不利于事务操作，这个明白了！
1如果connection.autocommit=true，每次‘直接’和database数据库连接，没有经过缓存了，是不是缓存的利用率下降啦?
2另外，autocommit=true以后，代码中的‘显式声明’的事务是不是不能起作用了？
sharpyuce 2008-08-06
  • 打赏
  • 举报
 回复
还有，和缓存没有一点关系的
sharpyuce 2008-08-06
  • 打赏
  • 举报
 回复
connection.autocommit=true

这个属性是说，如果是true的话，就是自动提交，比如
在一个业务中中，你有多个操作数据库的子业务，
例如
业务SuperA中有子业务suba,subb,subc.....
如果是自动的话，
suba操作成功 提交
subb操作失败 回滚
subc操作失败 回滚

按照我们的逻辑当SuperA中有某一环节操作失败的话，都应该回滚到没有操作之前
而当为true时，则为出现a成功 b,c失败 ,SuperA不具备了时务的特征，原子性等等

当不是true时，这时事务的管理提交给了spring，Spring的事务控制是以一个bean为单位的，
SuperA是bean中一个方法或者其他，这样当执行事务SuperA时，只要a,b,c...中一个失败，都
会认定是失败操作 roolback. 这样避免了脏数据的出现，也合乎了事务的特征。。

不知道能不能看明白。。。
sharpyuce 2008-08-06
  • 打赏
  • 举报
 回复
1如果connection.autocommit=true，每次‘直接’和database数据库连接，没有经过缓存了，是不是缓存的利用率下降啦?
2另外，autocommit=true以后，代码中的‘显式声明’的事务是不是不能起作用了？


1,和缓存没关系，当整合spring时，ORM一般都是hinernate，缓存级别都是在hibernate的xml文件中设置的，一级缓存session,2级缓存sessionFactory，如果不是用orm，纯JDBC的话，缓存级别只能在数据库端设置。所以与connection.autocommit= true无关。

2，显式声明，你是说在程序中设置
connection.setautocommit(false);
然后通过调用connection类的commit()与rollback()方法来人工的方式对事务进行管理？
如果是这样的话，你的事务时起作用的。
meadking 2008-08-05
  • 打赏
  • 举报
 回复
为何没有人回答呢？
奇怪
Hibernate的配置文件
在 javaweb 开发时会用到三大框架ssh 其中hibernate的使用要先配置一下映射的文件，你可以通过下载此代码作为参考
Hibernate配置文件.pdf
Hibernate配置文件.pdf
hibernate.properties
hibernate.properties # # Hibernate, Relational Persistence for Idiomatic Java # # License: GNU Lesser General Public License (LGPL), version 2.1 or later. # See the lgpl.txt file in the root directory or . # ###################### ### Query Language ### ###################### ## define query language constants / function names hibernate.query.substitutions yes 'Y', no 'N' ## select the classic query parser #hibernate.query.factory_class org.hibernate.hql.internal.classic.ClassicQueryTranslatorFactory ################# ### Platforms ### ################# ## JNDI Datasource #hibernate.connection.datasource jdbc/test #hibernate.connection.username db2 #hibernate.connection.password db2 ## HypersonicSQL hibernate.dialect org.hibernate.dialect.HSQLDialect hibernate.connection.driver_class org.hsqldb.jdbcDriver hibernate.connection.username sa hibernate.connection.password hibernate.connection.url jdbc:hsqldb:./build/db/hsqldb/hibernate #hibernate.connection.url jdbc:hsqldb:hsql://localhost #hibernate.connection.url jdbc:hsqldb:test ## H2 (www.h2database.com) #hibernate.dialect org.hibernate.dialect.H2Dialect #hibernate.connection.driver_class org.h2.Driver #hibernate.connection.username sa #hibernate.connection.password #hibernate.connection.url jdbc:h2:mem:./build/db/h2/hibernate #hibernate.connection.url jdbc:h2:testdb/h2test #hibernate.connection.url jdbc:h2:mem:imdb1 #hibernate.connection.url jdbc:h2:tcp://dbserv:8084/sample; #hibernate.connection.url jdbc:h2:ssl://secureserv:8085/sample; #hibernate.connection.url jdbc:h2:ssl://secureserv/testdb;cipher=AES ## MySQL #hibernate.dialect org.hibernate.dialect.MySQLDialect #hibernate.dialect org.hibernate.dialect.MySQLInnoDBDialect #hibernate.dialect org.hibernate.dialect.MySQLMyISAMDialect #hibernate.connection.driver_class com.mysql.jdbc.Driver #hibernate.connection.url jdbc:mysql:///test #hibernate.connection.username gavin #hibernate.connection.password ## Oracle #hibernate.dialect org.hibernate.dialect.Oracle8iDialect #hibernate.dialect org.hibernate.dialect.Oracle9iDialect #hibernate.dialect org.hibernate.dialect.Oracle10gDialect #hibernate.connection.driver_class oracle.jdbc.driver.OracleDriver #hibernate.connection.username ora #hibernate.connection.password ora #hibernate.connection.url jdbc:oracle:thin:@localhost:1521:orcl #hibernate.connection.url jdbc:oracle:thin:@localhost:1522:XE ## PostgreSQL #hibernate.dialect org.hibernate.dialect.PostgreSQLDialect #hibernate.connection.driver_class org.postgresql.Driver #hibernate.connection.url jdbc:postgresql:template1 #hibernate.connection.username pg #hibernate.connection.password ## DB2 #hibernate.dialect org.hibernate.dialect.DB2Dialect #hibernate.connection.driver_class com.ibm.db2.jcc.DB2Driver #hibernate.connection.driver_class COM.ibm.db2.jdbc.app.DB2Driver #hibernate.connection.url jdbc:db2://localhost:50000/somename #hibernate.connection.url jdbc:db2:somename #hibernate.connection.username db2 #hibernate.connection.password db2 ## TimesTen #hibernate.dialect org.hibernate.dialect.TimesTenDialect #hibernate.connection.driver_class com.timesten.jdbc.TimesTenDriver #hibernate.connection.url jdbc:timesten:direct:test #hibernate.connection.username #hibernate.connection.password ## DB2/400 #hibernate.dialect org.hibernate.dialect.DB2400Dialect #hibernate.connection.username user #hibernate.connection.password password ## Native driver #hibernate.connection.driver_class COM.ibm.db2.jdbc.app.DB2Driver #hibernate.connection.url jdbc:db2://systemname ## Toolbox driver #hibernate.connection.driver_class com.ibm.as400.access.AS400JDBCDriver #hibernate.connection.url jdbc:as400://systemname ## Derby (not supported!) #hibernate.dialect org.hibernate.dialect.DerbyDialect #hibernate.connection.driver_class org.apache.derby.jdbc.EmbeddedDriver #hibernate.connection.username #hibernate.connection.password #hibernate.connection.url jdbc:derby:build/db/derby/hibernate;create=true ## Sybase #hibernate.dialect org.hibernate.dialect.SybaseDialect #hibernate.connection.driver_class com.sybase.jdbc2.jdbc.SybDriver #hibernate.connection.username sa #hibernate.connection.password sasasa #hibernate.connection.url jdbc:sybase:Tds:co3061835-a:5000/tempdb ## Mckoi SQL #hibernate.dialect org.hibernate.dialect.MckoiDialect #hibernate.connection.driver_class com.mckoi.JDBCDriver #hibernate.connection.url jdbc:mckoi:/// #hibernate.connection.url jdbc:mckoi:local://C:/mckoi1.0.3/db.conf #hibernate.connection.username admin #hibernate.connection.password nimda ## SAP DB #hibernate.dialect org.hibernate.dialect.SAPDBDialect #hibernate.connection.driver_class com.sap.dbtech.jdbc.DriverSapDB #hibernate.connection.url jdbc:sapdb://localhost/TST #hibernate.connection.username TEST #hibernate.connection.password TEST #hibernate.query.substitutions yes 'Y', no 'N' ## MS SQL Server #hibernate.dialect org.hibernate.dialect.SQLServerDialect #hibernate.connection.username sa #hibernate.connection.password sa ## JSQL Driver #hibernate.connection.driver_class com.jnetdirect.jsql.JSQLDriver #hibernate.connection.url jdbc:JSQLConnect://1E1/test ## JTURBO Driver #hibernate.connection.driver_class com.newatlanta.jturbo.driver.Driver #hibernate.connection.url jdbc:JTurbo://1E1:1433/test ## WebLogic Driver #hibernate.connection.driver_class weblogic.jdbc.mssqlserver4.Driver #hibernate.connection.url jdbc:weblogic:mssqlserver4:1E1:1433 ## Microsoft Driver (not recommended!) #hibernate.connection.driver_class com.microsoft.jdbc.sqlserver.SQLServerDriver #hibernate.connection.url jdbc:microsoft:sqlserver://1E1;DatabaseName=test;SelectMethod=cursor ## The New Microsoft Driver #hibernate.connection.driver_class com.microsoft.sqlserver.jdbc.SQLServerDriver #hibernate.connection.url jdbc:sqlserver://localhost ## jTDS (since version 0.9) #hibernate.connection.driver_class net.sourceforge.jtds.jdbc.Driver #hibernate.connection.url jdbc:jtds:sqlserver://1E1/test ## Interbase #hibernate.dialect org.hibernate.dialect.InterbaseDialect #hibernate.connection.username sysdba #hibernate.connection.password masterkey ## DO NOT specify hibernate.connection.sqlDialect ## InterClient #hibernate.connection.driver_class interbase.interclient.Driver #hibernate.connection.url jdbc:interbase://localhost:3060/C:/firebird/test.gdb ## Pure Java #hibernate.connection.driver_class org.firebirdsql.jdbc.FBDriver #hibernate.connection.url jdbc:firebirdsql:localhost/3050:/firebird/test.gdb ## Pointbase #hibernate.dialect org.hibernate.dialect.PointbaseDialect #hibernate.connection.driver_class com.pointbase.jdbc.jdbcUniversalDriver #hibernate.connection.url jdbc:pointbase:embedded:sample #hibernate.connection.username PBPUBLIC #hibernate.connection.password PBPUBLIC ## Ingres ## older versions (before Ingress 2006) #hibernate.dialect org.hibernate.dialect.IngresDialect #hibernate.connection.driver_class ca.edbc.jdbc.EdbcDriver #hibernate.connection.url jdbc:edbc://localhost:II7/database #hibernate.connection.username user #hibernate.connection.password password ## Ingres 2006 or later #hibernate.dialect org.hibernate.dialect.IngresDialect #hibernate.connection.driver_class com.ingres.jdbc.IngresDriver #hibernate.connection.url jdbc:ingres://localhost:II7/database;CURSOR=READONLY;auto=multi #hibernate.connection.username user #hibernate.connection.password password ## Mimer SQL #hibernate.dialect org.hibernate.dialect.MimerSQLDialect #hibernate.connection.driver_class com.mimer.jdbc.Driver #hibernate.connection.url jdbc:mimer:multi1 #hibernate.connection.username hibernate #hibernate.connection.password hibernate ## InterSystems Cache #hibernate.dialect org.hibernate.dialect.Cache71Dialect #hibernate.connection.driver_class com.intersys.jdbc.CacheDriver #hibernate.connection.username _SYSTEM #hibernate.connection.password SYS #hibernate.connection.url jdbc:Cache://127.0.0.1:1972/HIBERNATE ################################# ### Hibernate Connection Pool ### ################################# hibernate.connection.pool_size 1 ########################### ### C3P0 Connection Pool### ########################### #hibernate.c3p0.max_size 2 #hibernate.c3p0.min_size 2 #hibernate.c3p0.timeout 5000 #hibernate.c3p0.max_statements 100 #hibernate.c3p0.idle_test_period 3000 #hibernate.c3p0.acquire_increment 2 #hibernate.c3p0.validate false ############################## ### Proxool Connection Pool### ############################## ## Properties for external configuration of Proxool hibernate.proxool.pool_alias pool1 ## Only need one of the following #hibernate.proxool.existing_pool true #hibernate.proxool.xml proxool.xml #hibernate.proxool.properties proxool.properties ################################# ### Plugin ConnectionProvider ### ################################# ## use a custom ConnectionProvider (if not set, Hibernate will choose a built-in ConnectionProvider using hueristics) #hibernate.connection.provider_class org.hibernate.connection.DriverManagerConnectionProvider #hibernate.connection.provider_class org.hibernate.connection.DatasourceConnectionProvider #hibernate.connection.provider_class org.hibernate.connection.C3P0ConnectionProvider #hibernate.connection.provider_class org.hibernate.connection.ProxoolConnectionProvider ####################### ### Transaction API ### ####################### ## Enable automatic flush during the JTA beforeCompletion() callback ## (This setting is relevant with or without the Transaction API) #hibernate.transaction.flush_before_completion ## Enable automatic session close at the end of transaction ## (This setting is relevant with or without the Transaction API) #hibernate.transaction.auto_close_session ## the Transaction API abstracts application code from the underlying JTA or JDBC transactions #hibernate.transaction.factory_class org.hibernate.transaction.JTATransactionFactory #hibernate.transaction.factory_class org.hibernate.transaction.JDBCTransactionFactory ## to use JTATransactionFactory, Hibernate must be able to locate the UserTransaction in JNDI ## default is java:comp/UserTransaction ## you do NOT need this setting if you specify hibernate.transaction.manager_lookup_class #jta.UserTransaction jta/usertransaction #jta.UserTransaction javax.transaction.UserTransaction #jta.UserTransaction UserTransaction ## to use the second-level cache with JTA, Hibernate must be able to obtain the JTA TransactionManager #hibernate.transaction.manager_lookup_class org.hibernate.transaction.JBossTransactionManagerLookup #hibernate.transaction.manager_lookup_class org.hibernate.transaction.WeblogicTransactionManagerLookup #hibernate.transaction.manager_lookup_class org.hibernate.transaction.WebSphereTransactionManagerLookup #hibernate.transaction.manager_lookup_class org.hibernate.transaction.OrionTransactionManagerLookup #hibernate.transaction.manager_lookup_class org.hibernate.transaction.ResinTransactionManagerLookup ############################## ### Miscellaneous Settings ### ############################## ## print all generated SQL to the console #hibernate.show_sql true ## format SQL in log and console hibernate.format_sql true ## add comments to the generated SQL #hibernate.use_sql_comments true ## generate statistics #hibernate.generate_statistics true ## auto schema export #hibernate.hbm2ddl.auto create-drop #hibernate.hbm2ddl.auto create #hibernate.hbm2ddl.auto update #hibernate.hbm2ddl.auto validate ## specify a default schema and catalog for unqualified tablenames #hibernate.default_schema test #hibernate.default_catalog test ## enable ordering of SQL UPDATEs by primary key #hibernate.order_updates true ## set the maximum depth of the outer join fetch tree hibernate.max_fetch_depth 1 ## set the default batch size for batch fetching #hibernate.default_batch_fetch_size 8 ## rollback generated identifier values of deleted entities to default values #hibernate.use_identifier_rollback true ## enable bytecode reflection optimizer (disabled by default) #hibernate.bytecode.use_reflection_optimizer true ##################### ### JDBC Settings ### ##################### ## specify a JDBC isolation level #hibernate.connection.isolation 4 ## enable JDBC autocommit (not recommended!) #hibernate.connection.autocommit true ## set the JDBC fetch size #hibernate.jdbc.fetch_size 25 ## set the maximum JDBC 2 batch size (a nonzero value enables batching) #hibernate.jdbc.batch_size 5 #hibernate.jdbc.batch_size 0 ## enable batch updates even for versioned data hibernate.jdbc.batch_versioned_data true ## enable use of JDBC 2 scrollable ResultSets (specifying a Dialect will cause Hibernate to use a sensible default) #hibernate.jdbc.use_scrollable_resultset true ## use streams when writing binary types to / from JDBC hibernate.jdbc.use_streams_for_binary true ## use JDBC 3 PreparedStatement.getGeneratedKeys() to get the identifier of an inserted row #hibernate.jdbc.use_get_generated_keys false ## choose a custom JDBC batcher # hibernate.jdbc.factory_class ## enable JDBC result set column alias caching ## (minor performance enhancement for broken JDBC drivers) # hibernate.jdbc.wrap_result_sets ## choose a custom SQL exception converter #hibernate.jdbc.sql_exception_converter ########################## ### Second-level Cache ### ########################## ## optimize cache for minimal "puts" instead of minimal "gets" (good for clustered cache) #hibernate.cache.use_minimal_puts true ## set a prefix for cache region names hibernate.cache.region_prefix hibernate.test ## disable the second-level cache #hibernate.cache.use_second_level_cache false ## enable the query cache #hibernate.cache.use_query_cache true ## store the second-level cache entries in a more human-friendly format #hibernate.cache.use_structured_entries true ## choose a cache implementation #hibernate.cache.region.factory_class org.hibernate.cache.infinispan.InfinispanRegionFactory #hibernate.cache.region.factory_class org.hibernate.cache.infinispan.JndiInfinispanRegionFactory #hibernate.cache.region.factory_class org.hibernate.cache.internal.EhCacheRegionFactory #hibernate.cache.region.factory_class org.hibernate.cache.internal.SingletonEhCacheRegionFactory hibernate.cache.region.factory_class org.hibernate.cache.internal.NoCachingRegionFactory ## choose a custom query cache implementation #hibernate.cache.query_cache_factory ############ ### JNDI ### ############ ## specify a JNDI name for the SessionFactory #hibernate.session_factory_name hibernate/session_factory ## Hibernate uses JNDI to bind a name to a SessionFactory and to look up the JTA UserTransaction; ## if hibernate.jndi.* are not specified, Hibernate will use the default InitialContext() which ## is the best approach in an application server #file system #hibernate.jndi.class com.sun.jndi.fscontext.RefFSContextFactory #hibernate.jndi.url file:/ #WebSphere #hibernate.jndi.class com.ibm.websphere.naming.WsnInitialContextFactory #hibernate.jndi.url iiop://localhost:900/
hibernate保存不到数据1
解决getHibernateTemplate().save ()不能将数据保存到数据库的问题JusterDu 2016-03-15 08:38:57 1857
Struts2.1.6+Spring2.5.6+Hibernate3.3.1框架整合常见错误
Struts2.1.6+Spring2.5.6+Hibernate3.3.1框架整合常见错误.txt 初学者开发常见错误！
Java EE

67,549

社区成员

225,860

社区内容

发帖
与我相关
我的任务
社区描述
J2EE只是Java企业应用。我们需要一个跨J2SE/WEB/EJB的微容器，保护我们的业务核心组件（中间件），以延续它的生命力，而不是依赖J2SE/J2EE版本。
社区管理员
  • Java EE
加入社区
  • 近7日
  • 近30日
  • 至今

加载中

查看更多榜单
社区公告
暂无公告

试试用AI创作助手写篇文章吧

+ 用AI写文章