关于mybatis if else if 条件判断SQL片段表达式取值和拼接问题

 <if test="seat_no != null and seat_no != '' ">  
		        AND seat_no = #{seat_no}  
		    </if>   

<choose>
		    <when test="……">
		    	……
		    </when>
		    <otherwise>
		    	……
		    </otherwise>
	    </choose>

<select id="findUsersByUser" resultType="cn.soboys.kmall.sys.entity.User">
        select tu.USER_ID,tu.USERNAME,tu.SSEX,td.DEPT_NAME,tu.MOBILE,tu.EMAIL,tu.STATUS,tu.CREATE_TIME,
        td.DEPT_ID
        from t_user tu left join t_dept td on tu.DEPT_ID = td.DEPT_ID

        <where>
            <choose>
                <when test="userParams.adminType==4">
                    and tu.ADMIN_TYPE_ID in(2,3)
                </when>
                <otherwise>
                       <include refid="search"></include> 
                </otherwise>
            </choose>
            
        </where>

    </select>
 <sql id="search">
         <if test="userParams.adminType==null or userParams.adminType==''">
             and tu.ADMIN_TYPE_ID in(0,1)
         </if>

         <if test="userParams.adminType != null and userParams.adminType != ''">
             and tu.ADMIN_TYPE_ID=#{userParams.adminType}
         </if>


         <if test="userParams.roleId != null and userParams.roleId != ''">
             and (select group_concat(ur.ROLE_ID)
             from t_user u
             right join t_user_role ur on ur.USER_ID = u.USER_ID,
             t_role r
             where r.ROLE_ID = ur.ROLE_ID
             and u.USER_ID = tu.USER_ID and r.ROLE_ID=#{userParams.roleId})
         </if>


         <if test="userParams.mobile != null and userParams.mobile != ''">
             AND tu.MOBILE =#{userParams.mobile}
         </if>
         <if test="userParams.username != null and userParams.username != ''">
             AND tu.USERNAME   like CONCAT('%',#{userParams.username},'%')
         </if>
         <if test="userParams.ssex != null and userParams.ssex != ''">
             AND tu.SSEX  =#{userParams.ssex}
         </if>
         <if test="userParams.status != null and userParams.status != ''">
             AND tu.STATUS =#{userParams.status}
         </if>
         <if test="userParams.deptId != null and userParams.deptId != ''">
             AND td.DEPT_ID =#{userParams.deptId}
         </if>
         <if test="userParams.createTime != null and userParams.createTime != ''">
             AND DATE_FORMAT(tu.CREATE_TIME,'%Y%m%d') BETWEEN substring_index(#{userParams.createTime},'#',1) and substring_index(#{userParams.createTime},'#',-1)
         </if>
     </sql>

<sql id="user_columns">
    `user_id`, `name`, `sex`, `age`
</sql>

<!-- 定义基础列 -->
<sql id="user_base_columns">
    `user_id`, `name`
</sql>
 
<!-- 定义一个SQL片段 -->
<sql id="user_columns">
    <include refid="user_base_columns"/>, `sex`, `age`
</sql>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
   "https://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.hxstrive.mybatis.sql.demo1.UserMapper">
   <!-- 映射结果 -->
   <resultMap id="RESULT_MAP" type="com.hxstrive.mybatis.sql.demo1.UserBean">
      <id column="user_id" jdbcType="INTEGER" property="userId" />
      <result column="name" jdbcType="VARCHAR" property="name" />
      <result column="sex" jdbcType="VARCHAR" property="sex" />
      <result column="age" jdbcType="INTEGER" property="age" />
   </resultMap>
 
   <!-- 定义一个SQL片段 -->
   <sql id="user_columns">
      `user_id`, `name`, `sex`, `age`
   </sql>
 
   <!-- 查询所有用户信息 -->
   <select id="findAll" resultMap="RESULT_MAP">
      select <include refid="user_columns" /> from `user`
   </select>
 
</mapper>

<select id="xxx" ...>
    select id,name,... from country
    <where>
        <if test="name != null and name != ''">
            name like concat('%', #{name}, '%')
        </if>
    </where>
</select>

<select id="xxx" ...>
    select id,name,... from country
    <bind name="nameLike" value="'%' + name + '%'"/>
    <where>
        <if test="name != null and name != ''">
            name like #{nameLike}
        </if>
    </where>
</select>

<bind name="username_bind" 
      value='@java.util.UUID@randomUUID().toString().replace("-", "")' />

<select id="xxx" ...>
    select id,name,... from country
    <where>
        <if test="name != null and name != ''">
            name like '${'%' + name + '%'}'
        </if>
    </where>
</select>

<foreach collection="list" item="item" index="index" separator="AND" open="(" close=")">

    <choose>
        <when test='item.cname.contains("select") or item.cname.contains("checkbox") or item.cname.contains("date")'>
            <if test='item.cname.contains("select") or item.cname.contains("checkbox")'>
                find_in_set(#{item.value},base.${item.cname})
            </if>

            <if test='item.cname.contains("date")'>
                DATE_FORMAT(base.${item.cname},'%Y-%m-%d') = DATE_FORMAT(#{item.value},'%Y-%m-%d')
            </if>
        </when>
        <otherwise>
            base.${item.cname} = #{item.value}
        </otherwise>
    </choose>
</foreach>