Python 官方文档:入门教程 => 点击学习
目录案例一:if-else案例二:if嵌套mybatis中if和choose的嵌套案例一:if-else 在mybatis的使用过程中,难免会存在使用if-else的逻辑,但是实际是
在mybatis的使用过程中,难免会存在使用if-else的逻辑,但是实际是没有这种语法的,提供了choose标签来替代这种语法
<select id="selectUserByState" resultType="com.bz.model.entity.User">
SELECT
*
FROM
user
WHERE
1=1
<choose>
<when test="state == 1">
AND name = #{name1}
</when>
<when test="state == 2">
AND name = #{name2}
</when>
<otherwise>
AND name = #{name3}
</otherwise>
</choose>
</select>
在实际的编码过程中会对一些条件进行重复判断,并对内深入if判断,这时就可以使用if嵌套
<select id="selectUserByState" resultType="com.bz.model.entity.User">
SELECT
*
FROM
user
WHERE
<if test=" gender!=null and gender!='' ">
<if test=" gender==male ">
and name=#{name}
</if>
</if>
</select>
<!-- public List<VadtaxShow> findList(VadtaxShow vadtaxShow); -->
<select id="findList" parameterType="com.cdqyzj_WC.Backstage.vaddedtax.domain.VaddeTax" resultType="com.cdqyzj_WC.Backstage.vaddedtax.domain.VaddeTax">
SELECT t.addedId,t.taxType,t.totalSales,t.outputTax,t.inputTax,t.entryAmount, t.amountTax,t.retentionTax,
t.createTime, t.taxTime,t.comId,c.comName,c.comType
FROM t_g_vaddedtax AS t JOIN t_ucompany AS c ON c.comId = t.comId
<where>
1=1
<if test="comType != '' and comType != null"> and c.comType = #{comType}</if>
<if test="taxTime != null and taxTime != ''"> and t.taxTime =#{taxTime} </if>
<if test="taxType != null and taxType != '' "> and t.taxType =#{taxType} </if>
<if test="comId != null and comId != '' and comId != 0 "> and t.comId =#{comId} </if>
<if test="start_times != null and end_times != null">
<choose>
<when test="middle_times != null">
and t.createTime in ('${start_times}','${middle_times}', '${end_times}' )
</when>
<otherwise>
and t.createTime in ('${start_times}','${end_times}' )
</otherwise>
</choose>
</if>
<if test="orderBy != null and orderType != '' ">
order by ${orderBy} ${orderType}
</if>
<if test="pageSize != 0 ">
limit ${startRows},${pageSize}
</if>
</where>
</select>
功能实现之后反思:要不我不对“middle_times”判空?这样不就不用嵌套了吗?
<!-- public List<VadtaxShow> findList(VadtaxShow vadtaxShow); -->
<select id="findList" parameterType="com.cdqyzj_WC.Backstage.vaddedtax.domain.VaddeTax" resultType="com.cdqyzj_WC.Backstage.vaddedtax.domain.VaddeTax">
SELECT t.addedId,t.taxType,t.totalSales,t.outputTax,t.inputTax,t.entryAmount, t.amountTax,t.retentionTax,
t.createTime, t.taxTime,t.comId,c.comName,c.comType
FROM t_g_vaddedtax AS t JOIN t_ucompany AS c ON c.comId = t.comId
<where>
1=1
<if test="comType != '' and comType != null"> and c.comType = #{comType}</if>
<if test="taxTime != null and taxTime != ''"> and t.taxTime =#{taxTime} </if>
<if test="taxType != null and taxType != '' "> and t.taxType =#{taxType} </if>
<if test="comId != null and comId != '' and comId != 0 "> and t.comId =#{comId} </if>
<if test="start_times != null and end_times != null">
and t.createTime in ('${start_times}','${middle_times}', '${end_times}' )
</if>
<if test="orderBy != null and orderType != '' ">
order by ${orderBy} ${orderType}
</if>
<if test="pageSize != 0 ">
limit ${startRows},${pageSize}
</if>
</where>
</select>
到此这篇关于详解mybatis中的if-else的嵌套使用的文章就介绍到这了,更多相关mybatis if-else嵌套内容请搜索编程网以前的文章或继续浏览下面的相关文章希望大家以后多多支持编程网!
--结束END--
本文标题: 详解mybatis中的if-else的嵌套使用
本文链接: https://lsjlt.com/news/153830.html(转载时请注明来源链接)
有问题或投稿请发送至: 邮箱/279061341@qq.com QQ/279061341
2024-03-01
2024-03-01
2024-03-01
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
回答
回答
回答
回答
回答
回答
回答
回答
回答
回答
0