page.xml 定义：

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 <block type="core/text_list" name="right" as="right" translate="label">

                <label>Right Column</label>             </block>

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在catalog.xml里用reference 来扩展定义：

首页右边栏：

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 <default>

<reference name="right">

            <block type="catalog/product_compare_sidebar" before="cart_sidebar" name="catalog.compare.sidebar" template="catalog/product/compare/sidebar.phtml"/>             <block type="core/template" name="right.permanent.callout" template="callouts/right_col.phtml">                 <action method="setImgSrc"><src>p_w_picpaths/media/col_right_callout.jpg</src></action>                 <action method="setImgAlt" translate="alt" module="catalog"><alt>Keep your eyes open for our special Back to School items and save A LOT!</alt></action>             </block>         </reference>

</default>

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具体商品详细页：

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 <!--

Product view -->

 <catalog_product_view translate="label">

        <label>Catalog Product View (Any)</label>

<reference name="right">

            <block type="catalog/product_list_related" name="catalog.product.related" before="-" template="catalog/product/list/related.phtml"/>         </reference>  </catalog_product_view>

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用before,after 选择器来决定区块的位置，before="-"表示位于最前面。