Improved communication performance in vehicular communication networks (VCN) is achieved by enabling additional computation and storage support at the levels of edge, fog, and cloud. Specifically, the edge/fog servers located near vehicles enable improved networking performance, especially in terms of load balancing and end-to-end delay. Recently, Software Defined Networking (SDN) in general and SDN-based edge/fog computing in particular have been employed in the context of VCN, enabling further communications performance improvements to be achieved with the help of SDN-based fog/edge computing in the VCN (SDV-F). This paper surveys a large number of innovative approaches proposed for communications performance enhancement in the context of SDV-F and categorizes them based on different aspects, including Artificial Intelligence (AI) and security support. The advantages and limitations of the proposed approaches in each category are highlighted. Finally, various directions that can be considered as promising research avenues by researchers in the future are presented and discussed.