String 参数 作为if 条件

Posted 2020-10-26 yangfei969

mybatis mapper.xml sql  当parameterType为String时 任何参数都必须为_parameter(比如原先为参数为key），若果没有_parameter,提示错误There is no getter of  ‘username‘ in java.lang.string

int pagingCount(String key);

 

<select id="pagingCount" resultType="int" parameterType="string">
         SELECT 
            count(1)
        FROM 
            users 
        WHERE 1=1
        <if test="key != null and ‘‘ != key">
            name = #{key} or username = #{key}
        </if>
     </select>

 

<select id="pagingCount" resultType="int" parameterType="string">
         SELECT 
            count(1)
        FROM 
            users 
        WHERE 1=1
        <if test="_parameter != null and ‘‘ != _parameter">
            and name = #{_parameter} or username = #{_parameter}
        </if>
     </select>