MyBatisの高度な検索

SQLSESSION取得

SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
bean.setDataSource(mysqlDataSource());
bean.setConfigLocation(new PathMatchingResourcePatternResolver().getResource("classpath:mybatis/mybatis-config.xml"));
bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/mysql/*.xml"));
bean.setTypeAliasesPackage("com.getword.entity");
sqlSessionFactory = bean.getObject();

一から一

道

ユーザーと役割が1対1の関係、真ん中のテーブルSys_user_roleであると仮定すると、

public class SysUser{
    private SysRole role;
    ...
}

<select id="findUserAndRoleById" resultType="SysUser">
    select
    u.id,
    u.userName userName,
    u.userPassword userPassword,
    r.id "role.id",
    r.roleName "role.roleName"
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    inner join sys_role r on r.id = ur.roleId
    where u.id = #{id}
</select>

第二の方法

resultmapに、と同様の方法を使用します

<resultMap id="userRoleMap" type="SysUser">
    <id property="id" column="id" />
    <result property="userName" column="userName" />
    <result property="userPassword" column="userPassword" />
    <result property="role.id" column="roleId" />
    <result property="role.roleName" column="roleName" />
</resultMap>
<select id="findUserAndRoleById" resultMap="userRoleMap">
    select
    u.id,
    u.userName userName,
    u.userPassword userPassword,
    r.id roleId,
    r.roleName roleName
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    inner join sys_role r on r.id = ur.roleId
    where u.id = #{id}
</select>

三つの方法、関連付対応

このように、マルチテーブルのクエリのために、フィールドは指定されたパッケージのラベルを発生します

<resultMap id="userRoleMap" type="SysUser">
    <id property="id" column="id" />
    <result property="userName" column="userName" />
    <result property="userPassword" column="userPassword" />
    <association property="role" columnPrefix="role" javaType="SysRole">
        <result property="id" column="Id" />
        <result property="roleName" column="Name" />
    </association>
</resultMap>
<select id="findUserAndRoleById" resultMap="userRoleMap">
    select
    u.id,
    u.userName userName,
    u.userPassword userPassword,
    r.id roleId,
    r.roleName roleName
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    inner join sys_role r on r.id = ur.roleId
    where u.id = #{id}
</select>

このresultMapを継承することができます

<resultMap id="userRoleMap" type="SysUser" extends="userMap">
    <result property="userPassword" column="userPassword" />
    <association property="role" columnPrefix="role" javaType="SysRole">
        <result property="id" column="Id" />
        <result property="roleName" column="Name" />
    </association>
</resultMap>
<select id="findUserAndRoleById" resultMap="userRoleMap">
    select
    u.id,
    u.userName userName,
    u.userPassword userPassword,
    r.id roleId,
    r.roleName roleName
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    inner join sys_role r on r.id = ur.roleId
    where u.id = #{id}
</select>

4つの方法、関連ネストされたクエリ、最も簡単な方法

<resultMap id="userMap" type="SysUser">
    <id property="id" column="id" />
    <result property="userName" column="userName" />
</resultMap>

<resultMap id="userRoleMap" type="SysUser" extends="userMap">
    <result property="userPassword" column="userPassword" />
    <association property="role" column="roleId" select="com.getword.dao.SysRoleDao.findById" />
</resultMap>
<select id="findUserAndRoleById" resultMap="userRoleMap">
    select
    u.id,
    u.userName userName,
    u.userPassword userPassword,
    r.id roleId
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    inner join sys_role r on r.id = ur.roleId
    where u.id = #{id}
</select>

表語文字

<resultMap id="userRoleMap" type="SysUser">
    <result property="userPassword" column="userPassword" />
    <association property="role" column="roleId" select="com.getword.dao.SysRoleDao.findById" />
</resultMap>
<select id="findUserAndRoleById" resultMap="userRoleMap">
    select
    *
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    where u.id = #{id}
</select>

多くの1つ

道

<resultMap id="userMap" type="SysUser">
    <id property="id" column="id" />
    <result property="userName" column="userName" />
    <result property="userPassword" column="userPassword" />
</resultMap>

<resultMap id="userRoleMap" type="SysUser" extends="userMap">
    <collection property="roles" javaType="SysRole" columnPrefix="role">
        <id property="id" column="Id" />
        <result property="roleName" column="Name" />
    </collection>
</resultMap>
<select id="findUserAndRoleById" resultMap="userRoleMap">
    select
    u.id,
    u.userName userName,
    u.userPassword userPassword,
    r.id roleId,
    r.roleName roleName
    from sys_user u
    inner join sys_user_role ur on u.id=ur.userId
    inner join sys_role r on r.id = ur.roleId
    where u.id = #{id}
</select>

同じIDのユーザーは、パケットに対応する、ユーザに分類され