The rapid increase of the world’s urbanization process has been improving citizens’ quality of living. Combining new technologies of smart government, smart healthcare, smart transportation and other services under a framework of smart city minimizes urbanization challenges. However, these services demand a large data technology to support the infrastructure of smart cities. It is a major benefit to using blockchain technology as a framework to integrate multiple technologies of smart city such as Internet of Thing, big data platforms and smart transportation to enhance the automation, security and decentral- ization of smart city services. However, querying the blockchain to retrieve a transaction record is one of the major limitation of blockchain systems. The operation requires scanning the ledger searching for the result. In this paper, we utilized different smart contract designs to support indexing and querying the blockchain for ride sharing data. We evaluated the complexity, measured by gas consumption of mined transactions for two smart contract designs, Catalog and Sparse smart contracts. Our experiments evaluate retrieving data from the blockchain for the two smart contracts designs.