The DataPub meetup featured guest speakers Chris Whong and Jonathan Leek who shared their experiences solving "urban mysteries" using open datasets. Chris discussed how he uses PostgreSQL to clean and aggregate the New York City subway system's turnstile data, reducing 14M records to 2M, and making it possible to analyze trends and ask meaningful questions. He also highlighted the importance of open datasets and his work with Qri Cloud, an open source project for versioning and sharing datasets. Jonathan Leek, a Data Architect at the St. Louis Regional Data Alliance, presented on building a regional analytics database to make public data more accessible and usable in the St. Louis region, focusing on residential and commercial property data. His team is working on "The Regional Entity Database," an open source ETL infrastructure and analytical database that can be extended to all types of public data and municipalities. Both speakers emphasized the importance of making public data accessible and usable for citizens, organizations, and policymakers.