Complex sentence: In December 2014, Google initially claimed that PSY's music video "Gangnam Style" exceeded the 32-bit integer limit for YouTube view count, necessitating YouTube to upgrade the variable to a 64-bit integer.
Split into simpler sentences: In December 2014 PSY's music video "Gangnam Style" exceeded the 32-bit integer limit for YouTube view count. This prompted YouTube to upgrade the variable to a 64-bit integer.