处理大于小于号的方法：
https://www.cnblogs.com/winner-0715/p/6132755.html
第一种方法：
用转义字符把">"和"<"替换掉，就没有问题了。
<if test="startTime != null "> AND order_date >= #{startTime,jdbcType=DATE} </if> <if test="endTime != null "> AND order_date <= #{endTime,jdbcType=DATE} </if>
注意下，这里的startTime，endTime都是Date类型的~
附：XML转义字符
| < | < | 小于号 |
| > | > | 大于号 |
| & | & | 和 |
| ' | ’ | 单引号 |
| " | " | 双引号 |
第二种方法：
因为这个是xml格式的，所以不允许出现类似">"这样的字符，但是可以使用<![CDATA[ ]]>符号进行说明，将此类符号不进行解析
mapper文件示例代码
<if test="startTime != null "> AND <![CDATA[ order_date >= #{startTime,jdbcType=DATE} ]]> </if> <if test="endTime != null "> AND <![CDATA[ order_date <= #{endTime,jdbcType=DATE} ]]> </if>
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附带问题：
使用情况：mybatis xml中写的mapper 对接的是postgresql数据库
问题：在同一个项目中不同的mapper.xml文件中，分别出现了>= 和<=的比较运算符，但是在一个xml中需要额外处理才能使用，一个xml文件中不需要额外处理>或者<符号可以直接使用
下面附上两个xml文件代码和截图，
1.
<?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.rollong.chinatower.server.persistence.mapper.FinanceReportMapper"> <resultMap id="financeBriefDataResultMap" type="com.rollong.chinatower.server.api.payload.finance.FinanceBriefData"> <id property="id" column="id"/> </resultMap> <select id="search" resultMap="financeBriefDataResultMap"> SELECT * FROM ( SELECT ( CAST ( partner.id AS VARCHAR ) || '@partner' ) AS ID, partner.id AS partnerId, project.id AS projectId, construction.id AS constructionId, NULL AS takerId, NULL AS maintenanceId, count(report.id) as reportsCount, sum(report.amount) as totalAmount, max(report.updated_at) as reportLatestUpdatedAt FROM "project"."project_construction_partners" AS partner LEFT JOIN "project"."project_construction" AS construction ON partner.construction_id = construction.id LEFT JOIN "project"."projects" AS project ON construction.project_id = project.id LEFT JOIN "finance"."finance_reports" as report on partner.id = report.partner_id WHERE #{isConstruction} = TRUE AND construction.deleted_at IS NULL <if test="null != partnerType"> AND partner.name = '${partnerType}' </if> <if test="null != provinceId"> AND project.province_id = #{provinceId} </if> <if test="null != cityId"> AND project.city_id = #{cityId} </if> <if test="null != districtId"> AND project.district_id = #{districtId} </if> <if test="null != subCompanyId"> AND project.sub_company_id = #{subCompanyId} </if> <if test="null != thirdPartCompanyId"> AND partner.third_part_id = #{thirdPartCompanyId} </if> <if test="null != leaderEmployeeId"> AND partner.leader_employee_id = #{leaderEmployeeId} </if> <if test="null != workerEmployeeId"> AND exists( select 1 from "third_part"."worker_involved_constructions" as involved where involved.worker_id = #{workerEmployeeId} AND involved.project_partner_id = partner.id ) </if> <if test="null != reportStatus"> AND exists( select 1 from "finance"."finance_reports" as r where r.partner_id = partner.id <choose> <when test="'Submit' == reportStatus"> and r.approved_at is null and r.rejected_at is null and r.paid_at is null </when> <when test="'Approved' == reportStatus"> and r.approved_at is not null and r.rejected_at is null and r.paid_at is null </when> <when test="'Rejected' == reportStatus"> and r.approved_at is null and r.rejected_at is not null and r.paid_at is null </when> <when test="'Paid' == reportStatus"> and r.paid_at is not null </when> </choose> ) </if> <if test="null != keyword"> AND project.name like #{keyword} </if> GROUP BY partner.id,project.id,construction.id UNION SELECT ( CAST ( taker.ID AS VARCHAR ) || '@maintenance' ) AS ID, NULL AS partnerId, project.ID AS projectId, NULL AS constructionId, taker.ID AS takerId, maintenance.ID AS maintenanceId, count(report.id) as reportsCount, sum(report.amount) as totalAmount, max(report.updated_at) as reportLatestUpdatedAt FROM "project"."project_maintenance_takers" AS taker LEFT JOIN "project"."project_maintenance" AS maintenance ON taker.maintenance_id = maintenance.id LEFT JOIN "project"."projects" AS project ON maintenance.project_id = project.id LEFT JOIN "finance"."finance_reports" as report on taker.id = report.taker_id WHERE #{isMaintenance} = TRUE AND maintenance.deleted_at IS NULL AND taker.deleted_at IS NULL <if test="null != provinceId"> AND project.province_id = #{provinceId} </if> <if test="null != cityId"> AND project.city_id = #{cityId} </if> <if test="null != districtId"> AND project.district_id = #{districtId} </if> <if test="null != subCompanyId"> AND project.sub_company_id = #{subCompanyId} </if> <if test="null != thirdPartCompanyId"> AND taker.third_part_id = #{thirdPartCompanyId} </if> <if test="null != leaderEmployeeId"> AND taker.leader_employee_id = #{leaderEmployeeId} </if> <if test="null != workerEmployeeId"> AND exists( select 1 from "third_part"."worker_involved_maintenance" as involved where involved.worker_id = #{workerEmployeeId} AND involved.taker_id = taker.id ) </if> <if test="null != reportStatus"> AND exists( select 1 from "finance"."finance_reports" as r where r.taker_id = taker.id <choose> <when test="'Submit' == reportStatus"> and r.approved_at is null and r.rejected_at is null and r.paid_at is null </when> <when test="'Approved' == reportStatus"> and r.approved_at is not null and r.rejected_at is null and r.paid_at is null </when> <when test="'Rejected' == reportStatus"> and r.approved_at is null and r.rejected_at is not null and r.paid_at is null </when> <when test="'Paid' == reportStatus"> and r.paid_at is not null </when> </choose> ) </if> <if test="null != keyword"> AND project.name like #{keyword} </if> GROUP BY maintenance.id,project.id,taker.id ) AS table_all WHERE TRUE <if test="minReportsCount != null"> AND table_all.reportsCount >= #{minReportsCount} </if> <if test="maxReportsCount != null"> AND table_all.reportsCount <= #{maxReportsCount} </if> <choose> <when test="sort == 'Latest'"> ORDER BY table_all.reportLatestUpdatedAt DESC </when> <when test="sort == 'AmountAsc'"> ORDER BY table_all.totalAmount ASC </when> <when test="sort == 'AmountDesc'"> ORDER BY table_all.totalAmount DESC </when> </choose> </select> </mapper>
2.
<?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.rollong.chinatower.server.persistence.mapper.OrderMealTimeMapper"> <resultMap id="OrderMealResult" type="com.rollong.chinatower.server.api.payload.canteen.OrderMealTime" autoMapping="true"> <result property="years" column="years"/> <result property="months" column="months"/> <result property="days" column="days"/> <result property="counts" column="counts"/> <result property="checkOut" column="checkOut"/> </resultMap> <select id="search" resultMap="OrderMealResult"> SELECT ors.year_meal AS years, ors.month_meal AS months, ors.day_meal AS days, SUM (ors.counts) AS counts, SUM (ors.checkd_out) AS checkOut FROM canteen.order_meal ors WHERE TRUE <if test="null != canteenId"> AND ors.canteen_id = #{canteenId} </if> <if test=" null != startY and null != startM and null != startD" > AND <![CDATA[ (ors.year_meal *10000 + ors.month_meal *100 + ors.day_meal) >= (#{startY}*10000+#{startM}*100+#{startD}) ]]> </if> <if test=" null != endY and null != endM and null != endD" > AND <![CDATA[ (ors.year_meal *10000 + ors.month_meal *100 + ors.day_meal) <= (#{endY}*10000+#{endM}*100+#{endD}) ]]> </if> GROUP BY ors.year_meal,ors.month_meal,ors.day_meal </select> </mapper>
【究竟是xml的问题/还是对接的数据库的问题/还是数据库中对于某些类型字段处理不一样】
如果有兴趣或者刚好知道，遇到过这种情况的 希望大家能给个反馈，多多交流！！