mybatis 判断字符是否相等
1.外面单引号 里面双引号表示字符串
<if test='showColumn == null or showColumn == "" '>
srr.id
</if>
<if test='showColumn != null and showColumn != "" and showColumn != "*"'>
srr.id,${showColumn}
</if>
<if test='showColumn != null and showColumn != "" and showColumn == "*"'>
${showColumn}
</if>
标签：字符,相等,srr,mybatis,showColumn,id From： https://www.cnblogs.com/yexuba/p/16824386.html