Shulou(Shulou.com)06/01 Report--

Pay attention to mysql.jar package version conflicts if you use an application container. (for example, the weblogic container comes with mysql, but the version is relatively low. It is recommended to use the mysql.jar package under your own application)

To_date-> date_format

WM_CONCAT-> > GROUP_CONCAT

Select * from dual-> > select'* 'from dual or select 1 from dual

Rownum-> limit

Delete-should delete a from TEST_TABLE a where a.ID =''when using an alias

Table names need to be the same case by default on the linux server, so all uppercase ones conform to the specification.

ROWNUM needs custom authoring.

Modify dialect. There is no BigDecimal,Long,Text in mysql default dialect.

Null is not supported for CHAR type

Custom dialect is required for reference

Package com.yourcompany

Import java.sql.Types

Import org.hibernate.Hibernate

Import org.hibernate.dialect.MySQLDialect

Public class MyDialect extends MySQLDialect {

Public MyDialect () {

Super ()

RegisterHibernateType (Types.DECIMAL, Hibernate.BIG_DECIMAL.getName ())

RegisterHibernateType (Types.LONGVARCHAR, Hibernate.STRING.getName ())

RegisterHibernateType (Types.BINARY, Hibernate.STRING.getName ())

RegisterColumnType (Types.CHAR, 255, "char ($l)")

RegisterHibernateType (Types.CHAR, Hibernate.STRING.getName ();}

}

Connection pool setting: timeBetweenEvictionRunsMillis:60000, the value needs to be smaller, and the performance of mysql database may be poor.

Mysql needs to set wait_timeout, otherwise there are many sleep processes in mysql, which will end within 8 hours by default.

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