Question

when trying to enable and reindex Product Flat Data – getting error from magento

The Flat Catalog module has a limit of 64 filterable and/or sortable
attributes. Currently there are 521 of them. Please reduce the number
of filterable/sortable attributes in order to use this module.

I can’t understand what this means and from where magento gets this values.
In attributes I have only 321 different attributes so from where magento gets value of 521 currently used and where it takes limit for 64 of them???

thnx.

Answer 1

The method Mage_Catalog_Model_Resource_Product_Flat_Indexer::prepareFlatTable() is throwing this exception, when your product has more than

<global>
    <catalog>
        <product>
            <flat>
                <max_index_count>64</max_index_count>
            </flat>
        </product>
    </catalog>
</global>

indexes. This maximum usually is defined in app/code/core/Mage/Catalog/etc/config.xml and matches the maximum number of 64 keys allowed by default mySQL installations, before they error with

ERROR 1069: Too many keys specified. Max 64 keys allowed

Your problem is not how many attributes your products have, but how many of them are filterable and/or sortable (except all your attributes are, of course).

Trace Mage_Catalog_Model_Resource_Product_Flat_Indexer::getFlatIndexes() to find out how Magento reaches a total of 521 indexes.

For a quick check you can also have a look at your catalog_eav_attribute table and check how many attributes are filterable (is_filterable = 1) and/or sortable (used_for_sort_by = 1)