Cannot read property '0' of undefined with pg 7

What you are doing?

I just upgraded to Sequelize 4.4.2 and node-postgres (pg) version 7.0.2

Then, when I call sync() to connecto the db and create tables. I get an error

It happens, for example, when I run this command:

models.sequelize.sync({force: true}).

What do you expect to happen?

Sequelize should connect to Postgres and the create tables.

What is actually happening?

TypeError: Cannot read property 'Symbol(Symbol.iterator)' of undefined
    at Promise.then.result (C:\test\node_modules\sequelize\lib\dialects\postgres\connection-manager.js:157:31)
    at tryCatcher (C:\test\node_modules\bluebird\js\release\util.js:16:23)
    at Promise._settlePromiseFromHandler (C:\test\node_modules\bluebird\js\release\promise.js:512:31)
    at Promise._settlePromise (C:\test\node_modules\bluebird\js\release\promise.js:569:18)
    at Promise._settlePromise0 (C:\test\node_modules\bluebird\js\release\promise.js:614:10)
    at Promise._settlePromises (C:\test\node_modules\bluebird\js\release\promise.js:693:18)
    at Async._drainQueue (C:\test\node_modules\bluebird\js\release\async.js:133:16)
    at Async._drainQueues (C:\test\node_modules\bluebird\js\release\async.js:143:10)
    at Immediate.Async.drainQueues (C:\test\node_modules\bluebird\js\release\async.js:17:14)
    at runCallback (timers.js:651:20)
    at tryOnImmediate (timers.js:624:5)
    at processImmediate [as _immediateCallback] (timers.js:596:5)

__Dialect: postgres __Database version: 9.6.2 (pg 7.0.2) __Sequelize version: 4.4.2

[ghost]

I just installed pg@6.4.1. it may be an issue related with the support for pg ^7.0.2

[dsullivan7]

I found that switching from findOrCreate to findCreateFind (documentation here) solved this issue for me