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每个Mapper接口对应一个mapper.xml文件，每个Mapper接口的方法，对一个mapper.xml文件的sql。
src/main/resource/com/ujcms/cms/ext/mapper/ExampleMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.ujcms.cms.ext.mapper.ExampleMapper">
<resultMap id="BaseResultMap" type="com.ujcms.cms.ext.domain.Example">
<id column="id_" jdbcType="INTEGER" property="id" />
<result column="name_" jdbcType="VARCHAR" property="name" />
<result column="description_" jdbcType="VARCHAR" property="description" />
<result column="height_" jdbcType="INTEGER" property="height" />
<result column="birthday_" jdbcType="TIMESTAMP" property="birthday" />
<result column="enabled_" jdbcType="CHAR" property="enabled" />
</resultMap>
<resultMap extends="BaseResultMap" id="ResultMap" type="com.ujcms.cms.ext.domain.Example" />
<sql id="selectAllJoin" />
<sql id="selectAllWhere" />
<select id="selectAll" resultMap="ResultMap">
<include refid="com.ujcms.cms.core.mapper.SeqMapper.Select_All">
<property name="tableName" value="ujcms_example" />
</include>
</select>
<select id="select" parameterType="java.lang.Integer" resultMap="ResultMap">
select
<include refid="Column_List" />
from ujcms_example t
where t.id_ = #{id,jdbcType=INTEGER}
</select>
<delete id="delete" parameterType="java.lang.Integer">
delete from ujcms_example
where id_ = #{id,jdbcType=INTEGER}
</delete>
<update id="update" parameterType="com.ujcms.cms.ext.domain.Example">
update ujcms_example
set name_ = #{name,jdbcType=VARCHAR},
description_ = #{description,jdbcType=VARCHAR},
height_ = #{height,jdbcType=INTEGER},
birthday_ = #{birthday,jdbcType=TIMESTAMP},
enabled_ = #{enabled,jdbcType=CHAR}
where id_ = #{id,jdbcType=INTEGER}
</update>
<insert id="insert" parameterType="com.ujcms.cms.ext.domain.Example">
insert into ujcms_example (id_, name_, description_, height_, birthday_, enabled_)
values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{description,jdbcType=VARCHAR}, #{height,jdbcType=INTEGER}, #{birthday,jdbcType=TIMESTAMP}, #{enabled,jdbcType=CHAR})
</insert>
<sql id="Column_List">
t.id_, t.name_, t.description_, t.height_, t.birthday_, t.enabled_
</sql>
</mapper>
其中BaseResultMap Column_List select update由代码生成器维护，不要修改，否则再次运行代码生成器时，会被覆盖。其余部分可以修改，也可以增加新的代码。
selectAll引用了com.ujcms.cms.core.mapper.SeqMapper.Select_All，用于根据查询解析器生成的查询信息，生成查询sql。
<sql id="selectAllJoin" />和<sql id="selectAllWhere" />标签内可以写一些额外的表连接条件和查询条件，会被包含进selectAll标签的sql里。
如果有关联关系，可以将关联关系写入ResultMap中，不要写在BaseResultMap里面。例如：
<resultMap id="BaseResultMap" type="com.ujcms.cms.ext.domain.Example">
...
<!-- 首先需要在表里面增加关联字段，代码生成器会生成此行代码 -->
<result column="user_id_" jdbcType="INTEGER" property="userId" />
...
</resultMap>
<resultMap extends="BaseResultMap" id="ResultMap" type="com.ujcms.cms.ext.domain.Example">
<association column="user_id_" javaType="com.ujcms.cms.core.domain.User" property="user" select="com.ujcms.cms.core.mapper.UserMapper.select" />
</resultMap>
src/main/resource/com/ujcms/cms/core/mapper/SeqMapper.xml
<sql id="Select_All">
SELECT
<if test="queryInfo != null and queryInfo.distinct">DISTINCT</if>
<include refid="Column_List" />
FROM
<choose>
<when test="queryInfo != null">${queryInfo.tableName}</when>
<otherwise>${tableName}</otherwise>
</choose>
t
<if test="queryInfo != null">
<foreach collection="queryInfo.joinTables" item="table">
JOIN ${table.tableName} ${table.tableAlias} ON ${table.leftId} = ${table.rightId}
</foreach>
</if>
<include refid="selectAllJoin" />
<where>
<if test="queryInfo != null">
<foreach collection="queryInfo.whereConditions" item="condition">
AND ${condition.column} ${condition.operator}
<choose>
<when test="condition.operator == 'IN' or condition.operator == 'NOT IN'">
<foreach close=")" collection="condition.value" index="index" item="item" open="(" separator=",">
#{item}
</foreach>
</when>
<when test="condition.operator != 'IS NULL'">#{condition.value}</when>
</choose>
</foreach>
<bind name="whereOrAndConditions" value="queryInfo.whereOrAndConditions" />
<foreach collection="whereOrAndConditions.keys" item="key">
AND (
<bind name="orAndConditions" value="whereOrAndConditions[key]" />
<if test="orAndConditions != null">
<foreach collection="orAndConditions.keys" item="andKey" separator="OR">
<bind name="andConditions" value="orAndConditions[andKey]" />
<foreach close=")" collection="andConditions" item="condition" open="(" separator="AND">
${condition.column} ${condition.operator}
<choose>
<when test="condition.operator == 'IN' or condition.operator == 'NOT IN'">
<foreach close=")" collection="condition.value" index="index" item="item" open="(" separator=",">
#{item}
</foreach>
</when>
<when test="condition.operator != 'IS NULL'">#{condition.value}</when>
</choose>
</foreach>
</foreach>
</if>
)
</foreach>
</if>
<include refid="selectAllWhere" />
</where>
<if test="queryInfo!=null and queryInfo.orderBy!=null">
ORDER BY ${queryInfo.orderBy}
</if>
</sql>