4. MyBatis several areas that can be optimized

Rather than optimization, it's better to make the configuration simpler.

One: The configuration of the connection database is placed in a single property file

Create a new Db.properties property file under the SRC path and put the database connection information in the file, and then import the property file reference in the Conf.xml file to be better managed.

1. Create a new db.properties file

2. Write attribute Information

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3. Import the properties file in Conf.xml

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4. Referencing values in the properties file

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Two: Define aliases for entity classes, simplifying references in SQL mapping files.

This is the case when you previously referred to the person type in the Personmapper.xml file.

Resulttype= "Com.mybatis.entities.Person"//package name +; class Name

This kind of thing is more complicated to write when it is quoted more often. Complex is certainly a simple method.

In Conf.xml, use this tag (<typeAliases></typeAliases>) to alias an entity class. You can then refer to this alias in the Personmapper.xml file.

There are two methods of aliases:

1. Alias the class directly

Add the following label to the <configuration> tab in the Conf.xml file

<typealiases><typealias type= "Com.mybatis.entities.Person" alias= "_person"/></typealiases>

Next alias is an alias, we can use it directly in the Personmapper.xml file _person.

<select id= "getpersons" parametertype= "int" resulttype= "_person" >select ID, name, age from person</select>

2. Aliases for Wrap

Add the following label to the <configuration> tab in the Conf.xml file

<typeAliases><!--<typealias type= "Com.mybatis.entities.Person" alias= "_person"/>--><package Name= "Com.mybatis.entities"/></typealiases>

Note: Using the package sub-label, the value of name fills in the packages name where the entity class resides. It is possible to refer directly to the class name when referencing it.

<select id= "Getperson" parametertype= "int" resulttype= "person" >select ID, name, age from person WHERE id=#{id}< /select>

I personally prefer the second method (to wrap aliases).

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4. MyBatis several areas that can be optimized