Product flat data reindexing problem in Magento.
A table in MySQL has a limitation of 65535 bytes of overall row length. It may severely limit the number of columns in a table when it has varchar/char columns. In Magento starting from 1.3 the products catalog in the “flat” mode suffers from this limitation depending on the number and combination of the product attributes that participate in the flat product index.
The workaround that stood out was setting “Used in Product Listing” = No: from your Magento Admin Panel.
Apparently, when I originally set up the store I was under the impression that this field always has to be set to Yes. Of course I want this attribute to be used in my product listing. Whats the point of creating an attribute that will not be used in the product listing, right? Well, no. This field controls if the attribute will be used in the “grid” or “list” view when showing multiple products per page. In my opinion you only need certain fields set to yes for those views, and its already preset when you set up magento for the first time. Fields like, price, special price, name and short description. Not EVERY attribute!
Go to your phpmyadmin and run sql with below code:
update ‘catalog_eav_attribute’ as anw
left join eav_attribute as mas on anw.attribute_id = mas.attribute_id
set anw.used_in_product_listing = 0
where anw.used_in_product_listing = 1 and is_user_defined = 1
Then just reindex from your admin panel hope solved your problem.
if you face any problem just reply me.