hibernate mysql problems - mysql

there are 2 things i wish to do mysql database from hibernate.cfg.xml;
To have utf8 characters so it can save character č,ć,ž,đ,š and repoduse them as thay are, not as ? in tapestry application.
fix for the com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException
No operations allowed after connection closed.Connection was
implicitly closed due to underlying exception/error: ** BEGIN NESTED
EXCEPTION ** com.mysql.jdbc.exceptions.jdbc4.CommunicationsException
MESSAGE: The last packet successfully received from the server
was48709 milliseconds ago.The last packet sent successfully to the
server was 48709 milliseconds ago, which is longer than the server
configured value of 'wait_timeout'. You should consider either
expiring and/or testing connection validity before use in your
application, increasing the server configured values for client
timeouts, or using the Connector/J connection property
'autoReconnect=true' to avoid this problem.
my hibermate.cfg.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost/200</property>
<property name="connection.username">root</property>
<property name="connection.password">123</property>
<property name="connection.autoReconnectForPools">true</property>
<property name="connection.autoReconnect">true</property>
<property name="hibernate.connection.useUnicode">true</property>
<property name="hibernate.connection.characterEncoding">UTF-8</property>
<property name="hibernate.connection.charSet">UTF-8</property>
<property name="connection.pool_size">5</property>
<property name="hbm2ddl.auto">update</property>
<!-- Print SQL to stdout. -->
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<property name="use_sql_comments">true</property>
<property name="generate_statistics">true</property>
<property name="hibernate.transaction.flush_before_completion">false</property>
<!-- Mapping files -->
<mapping class="domaci.entities.Korisnik"/>
<mapping class="domaci.entities.Magazin"/>
<mapping class="domaci.entities.Rubrika"/>
<mapping class="domaci.entities.Strana"/>
</session-factory>
</hibernate-configuration>

well, in your cfg file for that č,ć,ž,đ,š characters you need to set character set to utf-8 also:
default-character-set=utf8
or something like this,..., I'm not really into this hibernate stuff but I know that you need to do this. "charset=utf-8"

also have Increased server timeout with next commands:
set ##global.wait_timeout=31536000
set ##session.wait_timeout=31536000

Related

How to set MariaDb Driver properties using hibernate

I am using aurora mysql db. I am using mariadb connector j with hibernate.
I am using "org.mariadb.jdbc.Driver".I want to set following properties of this driver using hibernate cfg file.
set read only on connetion so that it will fetch data from read replica.
pooling mechanism of mariadb driver(minPoolSize , maxPoolSize etc.)
hibernte.cfg.xml
<hibernate-configuration>
<session-factory>
<!-- SQL Dialect -->
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
<!-- Database Connection Settings -->
<property name="hibernate.connection.driver_class">org.mariadb.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql:aurora://xxxxx:3306/dbname</property>
<property name="hibernate.connection.username">xxxxx</property>
<property name="hibernate.connection.password">xxxxx</property>
<property name="hibernate.connection.assureReadOnly">true</property>
<property name="hibernate.connection.autoReconnect">true</property>
<property name="hibernate.connection.autocommit">false</property>
<property name="hibernate.connection.maxPoolSize">5</property>
<property name="hibernate.connection.minPoolSize">2</property>
<property name="hibernate.connection.poolName">MyConnectionPool</property>
<property name="hibernate.connection.pool">true</property>
<property name="hibernate.connection.maxIdleTime">7000</property>
<property name="show_sql">true</property>
<!-- Specifying Session Context -->
<property name="hibernate.current_session_context_class">org.hibernate.context.internal.ThreadLocalSessionContext</property>
<!-- Mapping With Model Class Containing Annotations -->
<mapping class="com.xxx.aurora.beans.xxx" />
<mapping class="com.xxx.aurora.beans.User" />
</session-factory>
</hibernate-configuration>
I am able to connect with aurora mysql, but not able to set the connection on readonly. My requirement is that I want to create the connection with read-only replica for read queries using single cluster end point.
I am taking reference form mariadb-connector-j
I am also wondering that can I use the maria db connection pool with hibernate, if yes then how?
Change these Lines
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
<property name="hibernate.connection.url">jdbc:mysql:aurora://xxxxx:3306/dbname</property>
to
<property name="dialect">org.hibernate.dialect.MariaDBDialect</property>
<property name="connection.url">jdbc:mariadb://xxxxxx:3306/dbname</property>

Why is Hibernate response not reflected when making direct changes in the database?

When I made direct changes in the database, it's not reflected in the webservices response on request, however it is working once I restart the server. How can I make changes work immediately?
My hibernate configuration file looks like this:
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect
</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver
</property>
<property name="hibernate.connection.url">
jdbc:mysql://localhost:3306/demo</property>
<property name="hibernate.connection.username">xxxx</property>
<property name="hibernate.connection.password">xxxx</property>
<property name="hibernate.cache.use_second_level_cache">true</property>
</session-factory>
</hibernate-configuration>
This is because you have use_second_level_cache set to true.
Change the value of use_second_level_cache to false and would hit db every time without using 2nd level cache

Problem with c3p0 and MySql wait_timeout

I'm getting com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.Connection was implicitly closed by the driver error after sometime in my webapp. That "sometime" was 8 hrs but i found out that by default, the server closes the connection after eight hours if nothing has happened. So i changed "wait_timeout" to 30 sec. and changed hibernate.c3p0.idle_test_period property in hibernate.cfg.xml to 10 sec
Here's my hibernate.cfg.xml properties
<property name="connection.pool_size">20</property>
<property name="hibernate.connection.zeroDateTimeBehavior">
convertToNull
</property>
<property>
name="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider
</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">50</property>
<property name="hibernate.c3p0.timeout">15</property>
<property name="hibernate.c3p0.max_idle_time">18</property>
<property name="hibernate.c3p0.max_statements">50</property>
<property name="hibernate.c3p0.idle_test_period">10</property>
Here's my c3p0 properties
c3p0.preferredTestQuery = SELECT 1;
But i'm still getting the same error

Problem with UTF-8 in Create Schema By Hibernate

this is My hibernate.hbm.xml
and I use MySQL
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/dbName?autoReconnect=true&useUnicode=true&characterEncoding=UTF-8</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">******</property>
<property name="hbm2ddl.auto">update</property>
<property name="hibernate.connection.useUnicode">true</property>
<property name="hibernate.connection.characterEncoding">UTF-8</property>
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<property name="hibernate.use_sql_comments">true</property>
<property name="current_session_context_class">thread</property>
<!-- configuration pool via c3p0-->
<property name="c3p0.acquire_increment">1</property>
<property name="c3p0.idle_test_period">100</property> <!-- seconds -->
<property name="c3p0.max_size">100</property>
<property name="c3p0.max_statements">0</property>
<property name="c3p0.min_size">10</property>
<property name="c3p0.timeout">100</property> <!-- seconds -->
<!-- DEPRECATED very expensive property name="c3p0.validate>-->
</session-factory>
</hibernate-configuration>
when I run my program for first time it creates Table in database but my problem is the Charset still is latin1_swedish_ci (latin) and don't be utf8 what should I change in hibernate.hbm.xml settings?
I resolved this problem by setting character-set-server option in my.cnf:
[mysqld]
character-set-server=utf8
The UTF-8 setting relates to the way that Hibernate configures its runtime connections to the database. I'm guessing it has no effect on the schema creation stuff, which is really a separate part of Hibernate altogether.
I find that the auto-DDL stuff is only really useful for generating an initial stab at the schema. I always take that DDL and modify it to be exactly what I want.

Hibernate, C3P0, Mysql -- Broken Pipe

MySQL seems to have an 8 hour time out on its connections. I'm running multiple WARs in Tomcat utilizing Hibernate for ORM. After 8 hours (i.e. overnight), I get broken pipes when it picks up an idle connection.
I've already traced through the code and made doubly sure I commit or rollback all transactions.
Here is my hibernate.cfg.xml
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.bytecode.use_reflection_optimizer">false</property>
<property name="hibernate.connection.driver_class">org.gjt.mm.mysql.Driver</property>
<property name="hibernate.connection.password"></property>
<property name="hibernate.connection.url">jdbc:mysql://localhost/test</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
<property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
<property name="hibernate.current_session_context_class">thread</property>
<!--property name="hibernate.show_sql">true</property>
<property name="hibernate.format_sql">true</property-->
<property name="c3p0.min_size">3</property>
<property name="c3p0.max_size">5</property>
<property name="c3p0.timeout">1800</property>
<property name="c3p0.preferredTestQuery">SELECT 1</property>
<property name="c3p0.testConnectionOnCheckout">true</property>
<property name="c3p0.idle_test_period">100</property> <!-- seconds -->
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<property name="cache.use_query_cache">false</property>
<property name="cache.use_minimal_puts">false</property>
<property name="max_fetch_depth">10</property>
<property name="hibernate.hbm2ddl.auto">update</property>
<!-- classes removed -->
</session-factory>
The parameter I thought would have fixed it was the c3p0.idle_test_period -- It defaults to 0. However, we still have the Broken Pipe issue after 8 hours of running. While there are multiple posts index via Google, none arrive at a satisfactory answer.
So it turns out I was missing a key line that enabled c3p0 (the c3p0 parameters I was tweaking were having no effect because Hibernate was using it's built in connection pool -- which it appropriately warns is not suitable for production). In hibernate 2.x, setting the hibernate.c3p0.max_size property enabled c3p0 connection pooling. However, in 3.x you must specify the following property --
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
Additionally, here are my final configuration parameters --
<property name="hibernate.c3p0.min_size">3</property>
<property name="hibernate.c3p0.max_size">5</property>
<property name="hibernate.c3p0.timeout">1800</property>
<property name="hibernate.c3p0.idle_test_period">100</property> <!-- seconds -->
It's rather unfortunate that both Hibernate and c3p0 have abysmal documentation in this regard.
There are two things going on here. You should read this article for more details, but the take-aways are:
You can adjust the MySQL wait_timeout setting to something larger than 8 hours, if desired.
The Hibernate settings should include "hibernate." before the "c3p0", e.g. hibernate.c3p0.idle_test_period instead of just c3p0.idle_test_period
This is a solution when you have a broken pipe because of combination of tomcat's wait_timeout=28800 sec(8h) and maxIdleTime=0 in c3p0:
I've changed the local tomcat wait_timeout via my.ini file to 120sec (2 min). And I placed the following:
maxIdleTime=100
idleConnectionTestPeriod=0 (same as default/as if it didn't exist)
other:
acquireIncrement=2
minPoolSize=2
maxPoolSize=5
maxIdleTimeExcessConnections=10
I had no problems with this setup.
I didn't need to use idleConnectionTestPeriod!
If tomcat's wait_timeout is 28800 sec, and maxIdleTime is 25200, it means that c3p0 will close the idle connection in 3600sec (1h) earlier, before tomcat throws a "broken pipe" exception. Isn't that right?!
As you can see I have no issues with providing only maxIdleTime.
Unfortunately, these:
maxIdleTime
idleConnectionTestPeriod
configuring_connection_testing
testConnectionOnCheckin
don't explain too much the corner cases.
And, btw, here is how to open the tomcat's my.ini file with Notepad++:
http://drupal.org/node/32715#comment-4907440
Cheers,
Despot
I've several problem -
- C3P0ConnectionProvider was not found
- I solve it by using the hibernate c3p0 version
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>3.5.6-Final</version>
</dependency>
<!-- c3p0 -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-c3p0</artifactId>
<version>3.3.1.GA</version>
</dependency>
- I have that wait_timeout issue on mysql. First I set /etc/my.cnf wait_timeout=10
then I changed the Idle time out value to lower than the wait_timeout value which < 10
That solved my problem.
<property name="hibernate.connection.provider_class" value="org.hibernate.connection.C3P0ConnectionProvider" /> <property name="hibernate.c3p0.acquire_increment" value="1" />
<property name="hibernate.c3p0.idle_test_period" value="28690"/>
<property name="hibernate.c3p0.timeout" value="1800" />
<property name="hibernate.c3p0.max_size" value="5" />
<property name="hibernate.c3p0.min_size" value="3" />
<property name="hibernate.c3p0.max_statement" value="50" />
<property name="hibernate.c3p0.preferredTestQuery" value="select 1;"/>
I was getting the same problem and it took time to figure out the solution.
I use Hibernate 4.0.1 and mysql 5.1(no spring framework) and I was facing the issue. First make sure that you configured the c3p0 jars properly which are essential.
I used these properties in hibernate.cfg.xml
<property name="hibernate.c3p0.validate">true</property>
<property name="hibernate.connection.provider_class">org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">20</property>
<property name="hibernate.c3p0.max_statements">50</property>
<property name="hibernate.c3p0.preferredTestQuery">SELECT 1;</property>
<property name="hibernate.c3p0.testConnectionOnCheckout">true</property>
<property name="hibernate.c3p0.idle_test_period">10</property>
<property name="hibernate.c3p0.acquireRetryAttempts">5</property>
<property name="hibernate.c3p0.acquireRetryDelay">200</property>
<property name="hibernate.c3p0.timeout">40</property>
But it's of no use 'cause C3p0 was still taking the default properties not the properties which I set in hibernate.cfg.xml, You can check it in logs. So, I searched many websites for right solution and finally I came up with this. remove the C3p0 properties in cfg.xml and create c3p0-config.xml in the root path(along with cfg.xml) and set properties as follows.
<c3p0-config>
<default-config>
<property name="automaticTestTable">con_test</property>
<property name="checkoutTimeout">40</property>
<property name="idleConnectionTestPeriod">10</property>
<property name="initialPoolSize">10</property>
<property name="maxPoolSize">20</property>
<property name="minPoolSize">5</property>
<property name="maxStatements">50</property>
<property name="preferredTestQuery">SELECT 1;</property>
<property name="acquireRetryAttempts">5</property>
<property name="acquireRetryDelay">200</property>
<property name="maxIdleTime">30</property>
</default-config>
</c3p0-config>
but if you run, ORM takes the jdbc connection but not C3p0 connection pool 'cause we should add these properties in hibernate.cfg.xml
<property name="hibernate.c3p0.validate">true</property>
<property name="hibernate.connection.provider_class">org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider</property>
now everything works fine(At least it worked fine for me) and the issue is solved.
check the following for references.
http://www.mchange.com/projects/c3p0/index.html#configuring_connection_testing
https://community.jboss.org/wiki/HowToConfigureTheC3P0ConnectionPool
I hope this solves your problem.