:6. Transform structure of the dataset
==Data Cleanup Progress==
The goal is to only have assignment records on utility patents. The patents in ptoproperty include alphanumerics which represent reissue and design patents as well as mistakes in the data input. Additionally, the documentids include application numbers or ids and publication numbers. The ptoproperty table stores the patent ids as character strings.
First the duplicates were dropped from the ptoproperty table creating ptoproperty_cleaned.
SELECT COUNT(*) FROM (SELECT DISTINCT * FROM ptoproperty) As T;
--27266638
SELECT COUNT(*) FROM ptoproperty_cleaned;
--27266638