iBatis Mapping a composite key

Composite Keys or Multiple Complex Parameters Properties

You might have noticed that in the above examples there is only a single key being used as specified in the resultMap by the column attribute. This would suggest that only a single column can be associated to a related mapped statement. However, there is an alternate syntax that allows multiple columns to be passed to the related mapped statement. This comes in handy for situations where a composite key relationship exists, or even if you simply want to use a parameter of some name other than #value#. The alternate syntax for the column attribute is simply {param1=column1, param2=column2, …, paramN=columnN}. Consider the example below where the PAYMENT table is keyed by both Customer ID and Order ID:


Example. Mapping a composite key

<resultMaps>  
    <resultMap id="select-order-result" class="order">    
        <result property="id" column="ORD_ID"/>    
        <result property="customerId" column="ORD_CST_ID"/>    
        …    
        <result property="payments" column="itemId=ORD_ID, custId=ORD_CST_ID"             select="selectOrderPayments"/>  
    </resultMap>
<resultMaps>

<statements>  
    <statement id="selectOrderPayments" resultMap="select-payment-result">    
    select 
        * 
    from 
        PAYMENT
    where
        PAY_ORD_ID = #itemId#
        and
        PAY_CST_ID = #custId#  
    </statement>
</statements>