Question

I am using mybatis to retrieve data from DB, the data returned is containing duplicate entries.

Required result : Column Name , Value

Expected result is : column1 value A
But returned result is : COLUMN1 value A , column1 value A.

Hope able to clarify my doubt.

Can anybody tell me why it is happening?

<select id="getContentMap" resultType="map" parameterType="map">
            select planId,location_qualifier  from disclaimer_disclosure_content where 
            <choose>
                <when test="plan_id != null">
                    plan_id = #{plan_id}
                </when>
                <when test="product_id != null">
                    product_id = #{product_id}
                </when>
                <otherwise>
                    issuer_id = #{issuer_id}
                </otherwise>
            </choose>
             and effective_date >= #{effective_date} 
             and location_qualifier LIKE  CONCAT('%' , #{location_qualifier} , '%') 
        </select>

Answer 1

The issue you are seeing is a bug in MyBatis 3 up until release 3.0.6: http://code.google.com/p/mybatis/issues/detail?id=303.

After that release you get the answer I outlined in my other answer (which was done with MyBatis 3.1.1).

You have four options:

1. Just ignore it and only grab the uppercase or lowercase entries
2. Upgrade to at least 3.0.6
3. Stop using map as resultType and move to a POJO domain object
4. Use the workaround below:

workaround for MyBatis < 3.0.6

Use full uppercase column aliases and they will only show up once (as uppercase) in your map:

<select id="getContentMap" resultType="map" parameterType="map">
  select plan_id as PLAN_ID, location_qualifier as LOCATION_QUALIFIER from disclaimer_disclosure_content
  where
  <!-- SNIP: is the same as you had -->
</select>

This results in the output:

{PLAN_ID=2, LOCATION_QUALIFIER=Bar}

(or something similar depending on exactly how your select looks).