选择性更新

<insert id="insertSelective" parameterType="com.dream.biz.model.entity.fixed.Stock" >
    insert into t_stock
    <trim prefix="(" suffix=")" suffixOverrides="," >
      <if test="id != null" >
        id,
      </if>
      <if test="status != null" >
        status,
      </if>
      <if test="assetClassifyId != null" >
        asset_classify_id,
      </if>
      <if test="assetId != null" >
        asset_id,
      </if>
      <if test="assetItemId != null" >
        asset_item_id,
      </if>
      <if test="name != null" >
        name,
      </if>
      <if test="num != null" >
        num,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides="," >
      <if test="id != null" >
        #{id,jdbcType=BIGINT},
      </if>
      <if test="status != null" >
        #{status,jdbcType=VARCHAR},
      </if>
      <if test="assetClassifyId != null" >
        #{assetClassifyId,jdbcType=BIGINT},
      </if>
      <if test="assetId != null" >
        #{assetId,jdbcType=BIGINT},
      </if>
      <if test="assetItemId != null" >
        #{assetItemId,jdbcType=BIGINT},
      </if>
      <if test="name != null" >
        #{name,jdbcType=VARCHAR},
      </if>
      <if test="num != null" >
        #{num,jdbcType=VARCHAR},
      </if>
    </trim>
  </insert>