<if test="distinct"> distinct </if>

Sorry, as an AI language model, I am unable to determine the context of this code snippet. Could you please provide more information or code surrounding this line?

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<if test="distinct">

I'm sorry, but this code snippet is not complete. Can you please provide more context or information on what you are trying to accomplish with the "distinct" test?

<mapper namespace="com.dao.CommonDao"> <select id="getOption" resultType="String" > SELECT distinct ${column} FROM ${table} where ${column} is not null and ${column} !='' <if test = "level != null"> and level=#{level} </if> <if test = "parent != null"> and parent=#{parent} </if> </select>

这段代码是一个 MyBatis 的 Mapper XML 文件，对应的 Mapper 接口是 com.dao.CommonDao。该文件中定义了一个 select 标签，用于查询某个表中某个字段的去重值。具体 SQL 语句如下：

SELECT distinct ${column} FROM ${table} 
where ${column} is not null and ${column} !='' 
<if test = "level != null"> 
and level=#{level} 
</if> 
<if test = "parent != null"> 
and parent=#{parent} 
</if>

其中，${column} 和 ${table} 是 SQL 语句中的占位符，需要在执行时替换为具体的字段名和表名。同时，该 SQL 语句还支持两个可选参数 level 和 parent，用于对查询结果进行过滤。最后，该 SQL 语句的查询结果类型是 String 类型。