I’m having this same issue but I didn’t have caching on. I deleted the /var/cache/ folder anyway, but I’m still getting this.
This happened after I merged in some tables from another magento install. Both are the same version, (1.5.10) and the error has only so far appeared in the backend when I click to manage products.
Also, when I tried to reindex all tables in Index Management. I get the same error, but this time in a friendly red error bar and the “Stock Status” index is in the “processing” stage.
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