Sergey Olontsev@olontsevData EngineerFollow BadgesProblem SolvingCPPJavaPythonSql CertificationsCertificate: SQL (Basic)VerifiedskillWork Experienceolontsev has not updated employment details yet.Educationolontsev has not updated education details yet.LinksLinkedinhttp://ru.linkedin.com/in/sergeyolontsev/ Skillsolontsev has not updated skills details yet.