TypeError: Object 1427615739.9614 has no method 'indexOf'

I set up models for a sqlite database using sequelize.js with node. Everything works fine when I manually enter data in the database for test purposes, but as soon as I use R or Python to enter data, I get this error when I try to fetch data fro the database in node with sequelize:

TypeError: Object 1427615739.959424 has no method 'indexOf'